Early Muslim expansion

Almost 1400 years ago the ancient and prosperous lands of the Middle East were on the verge

of a conflict of 3 empires and 3 religions: 2 of them fighting a constant, bloody, and

fruitless war for centuries, one a newcomer looking to put its mark. The newcomer was

the Rashidun Caliphate and its arrival would change the history of the region and the world

forever. The Roman state was almost constantly at war with the Iranian empires ever since the two

entities touched borders in the 60s BC, as the Parthian empire achieved a famous victory

at Carrhae. The Roman Republic transitioned into the Empire and then this Empire’s Western

portion was lost to foreign invasions, leaving only the Eastern Roman Empire, while the Parthian

empire was replaced by the Sassanid Empire, but even then these two states continued to

fight. In the 3rd century AD, another factor was

introduced to these conflicts – the Ghassanids and the Lakhmids. These two Arab tribal confederations

migrated from modern Yemen and became the vassal states of the Eastern Roman Empire and the Sassanids respectively. They participated in the Roman-Sassanid wars, often as scouts

or raiders detached from the armies, or as light cavalry units within the armies, while

also defending both empires from the Arab tribal raids from the south.

The populations of these kingdoms worshiped traditional Arab paganism and monophysite Christianity, and the latter created tensions with their suzerains, as the Sassanids were

sure that any Christian influence may strengthen their Roman enemies, while the Romans adhered

to miaphysite Orthodox Christianity, which considered monophysitism to be heretical.

The Roman attempts to suppress monophysitism caused the Ghassanids to rebel against them in the late 6th-early 7th century, and weakened Roman support in the area.

On the other hand, religious tensions between the Lakhmids and the Sassanids were compounded

by the attempts of shah Khosrow II to control the region directly. In 602 he captured and

executed the Lakhmid king Al-Nu'man III, turning the kingdom into a province administered by

a governor. That forced the Lakhmid tribes to ask their Arab brethren to the south for

help. Although the allied forces managed to defeat the Sassanid army at Dhi Qar in 609,

the Sassanids were able to keep the province under their rule. This sequence of events not only created divided loyalties among the Arab tribes in the region, but effectively

stripped the Sassanid border of its traditional buffer.

Despite that, the Sassanids were still very strong. In 602 they used the internal strife

within the Eastern Roman Empire as a pretense to declare war. The Sassanids scored a number

of impressive victories in the first years of the war, and although the Roman noble Heraclius

took the throne in 611 and started to stabilize the situation, he wasn’t able to slow down

the enemy completely; by 621 the Sassanids controlled the South Caucasus, the Levant,

Egypt and most of Anatolia, which marked the largest extent of their territory.

Even though Emperor Heraclius was forced to fight against the Avars in Europe too, he was able to gain some momentum by winning 2 battles against the Sassanids between 622

and 625. According to some sources, Khosrow enlisted all men capable of fighting and turned

the tide again: in 626 the army under Shahrbaraz besieged the capital of the empire, Constantinople,

supported by the Avars and Sclaveni from Europe. The Roman empire was on the brink of destruction,

but the defenders of the capital persevered. This was the turning point in the war, as

in 627 Heraclius entered an alliance with the leader of the Western Turkic Khaganate, Tong Yabghu, and together they invaded Iranian heartland. Heraclius defeated the Sassanids

at Nineveh in 627, and threatened the capital Ctesiphon in 628, which prompted the nobles

to overthrow Khosrow. His son Kavad II became the next shah, and signed a peace treaty with

Heraclius. The Sassanids paid a war indemnity, but otherwise, the conflict achieved nothing,

and the two exhausted empires returned to the pre-war borders.

Meanwhile to the south, the Arabian Peninsula was going through an upheaval. The population

Rise of the Rashidun Caliphate

of this peninsula worshipped many religions, from the traditional Arab pagan beliefs to Zoroastrianism, Judaism, and Christianity. The Sassanids controlled the province of Mazun

and the eastern portion of Yemen, while the deserts in the central and northern parts of the region were ruled by the nomadic Bedouin Arabs. Their brethren resided in the rich

merchant city-states in Hijaz. One of these city-states called Mecca was

both a religious and economic center governed by the Quraysh tribe, trading mostly spices

with Axum, the Romans, and the Sassanids. In 570 a boy called Muhammad was born in the

Quraysh tribe. As a young man, Muhammad spent his time as a merchant, probably participating

in and then leading trade caravans all over the region. As is often the case with traders,

Muhammad would meet and converse with members of various religions on his travels.

According to the later sources, he started receiving divine revelations sometime in 610.

Soon this new prophet began spreading the message of a new religion – Islam - in his home city of Mecca. However, the Meccans didn’t receive it well and in 614 they started to

persecute adherents of Islam. All this prompted Muhammad and his followers – the Muslims

- to emigrate to Medina in 622. This started a war between the Muslims and Mecca, and by

629 the latter lost, and was conquered. According to the early Muslim sources, at

this point, sometime in 628, Muhammad sent envoys to the neighboring states urging their

leaders to join Islam and bow to the one God – Allah. The Sassanid shah Kavad insulted

the Muslim envoy, while the one sent to the Romans was killed in Ghassanid territory.

This prompted an attack by a small Muslim army, which was defeated by the Ghassanids and Romans in September of 629 at Mutah. The same sources claim that Muhammad decided to

lead a 30,000 strong army into the Byzantine territory to retaliate, and took the city

of Tabuk. However, most modern sources do not agree with this account of events.

In any case, the conquests of Muhammad in Arabia continued. By 631 most of the Arabian

Peninsula was under Muslim control. Muhammad passed away a year later. There are conflicting

sources regarding the succession process, but one of the closest allies of Muhammad – Abu Bakr - became his successor, with the title of Caliph; he was the first of the

Rashidun Caliphs. In the meantime, Kavad II, who became the

Sassanid shah in February of 628, immediately started killing his brothers to secure the

throne, which resulted in deepening disagreements between the Persian and Parthian nobles. Kavad

died of the plague in September, and although his 8-year-old son became the next shah as

Ardashir III, the empire was controlled by a member of the Parthian clique, the vizier

Mahadharjushnas. This deeply concerned the Persian party, and so it allied with Khosrow’s

general Shahrbaraz. The latter attacked took the capital in April of 630, killing Ardashir

and Mahadharjushnas, and becoming the shah. The Sassanid realm was now in a state of civil

war. Using all that the governors of Yemen and

Mazun declared their independence from Ctesiphon, which made them easy prey for the rising caliphate.

Just 40 days after Shahrbaraz took the throne, he was killed and the leader of the Parthian

faction, Farrukh Hormizd, raised Khosrow’s daughter Boran to the throne. This first queen

in Sassanid history was overthrown by the son of Shahrbaraz, Shapur, a few months later.

To stop the war between the factions, Farrukh offered a marriage between Shapur and another

daughter of Khosrow, Azarmidokht, but the latter refused and the noble usurped the throne

for himself in the late 630. He would be killed by the supporters of Azarmidokht in 631, after

which she took the throne for herself. Farrukh’s son Rostam marched his troops to Ctesiphon

to avenge his father, defeating Azarmidokht’s armies along the way. After taking the capital

he restored Boran as the queen. The ruling alliance of Boran and Rostam managed

to convince the leader of the Persian clique Piruz to stop the hostilities. However, after

Rostam left the capital for the frontier, Firuzan killed Boran in June of 632. Rostam

then marched for the capital again. According to some sources, the armies of both Firuzan

and Rostam were tired of the bloodshed, and forced their generals to reach an accord.

One of the last members of the house of Sasan, the 8-year-old grandson of Khosrow II, was

crowned as Yazdegerd III. Although the civil war was now over, the Sassanid realm was extremely

vulnerable, as the Parthian clique basically controlled the northeastern portion of the

empire, while Turkic raiders attacked from the Caucasus and Central Asia.

At the same time, the first Caliph Abu Bakr sent a portion of his army under Usama ibn

Zaid to raid the Ghassanids in June of 632, possibly checking if the Byzantine frontier

was well defended. The death of Muhammad and the departure of this army made a big number

of newly conquered Arab tribes think that the Caliphate was fragile, and in July all

of the Peninsula save for Hijaz rebelled against Abu Bakr in what was called the Ridda War

or the War of Apostasy, as many rebel groups were led by people who declared themselves

prophets. The situation was most dire around Medina,

as the rebels threatened the second most important city of the new realm in late July. However,

Abu Bakr swiftly marched to the area and defeated the rebels in early August. That gave enough

time for the army, which was sent north and defeated a small Ghassanid army around Mu’tah,

to return. Abu Bakr proved to be a talented commander:

instead of uniting his armies and marching on each of the rebel groups separately, which would have allowed the rebels to attack his rear with impunity, he divided his army into

smaller groups, and these units attacked the enemies around the Peninsula. This strategy

worked to perfection and by March of 633, the Caliph’s rule over the entire region

was restored. It is difficult to assess how much the caliphate lost in terms of manpower,

but the sources underline that the generals and troops gained invaluable experience in

this conflict. While the Ridda Wars were going on, the leader of the Arab Bani Bakr tribe, Muthanna bin Harithah, was raiding the Sassanid territories

in southern Iraq. The Sassanid civil wars made this frontier subject to attacks, and

Muthanna, who adopted Islam sometime in the 630s, informed Abu Bakr of this fact in early

633. The caliph decided that it is a good time

to take over Iraq, and one of his main generals during the Ridda Wars – Khalid ibn al-Walid

- was ordered to invade the region. Khalid was able to recruit an army of 18,000 at his

base at Yamamah and left for Iraq in late March 633. A letter was sent to the Sassanid

Battle of the Chains

governor of Dast Meisan – Hormozd - demanding his surrender. Hormozd obviously didn’t,

but sent a letter to the capital, asking shah Yazdegerd III for reinforcements.

This letter was probably a trick by Khalid, as Hormozd gathered his 20,000 and marched

out of the capital of the governorship, Uballa, to defend the crucial road from Yamamah near

Kazima. Khalid, however, moved his troops through the desert and threatened Hufeir.

The Sassanid leader was informed of this and had to march towards Hufeir via Uballa. According

to the Muslim sources, that was exactly what Khalid was hoping would happen; despite the

civil wars, Sassanid armies were still stronger, as their armor and weaponry made them superior,

and the only tangible advantage Caliph’s forces had was their mobility. Khalid was

going to use this mobility to tire the sassanid army. This would become one of the most important

elements of the early Muslim expansion – their mobility and aggression were forcing their foe to defend multiple cities and fortresses, as it was never clear where the Arabs would

strike. By the time Hormozd reached Hufeir, Khalid

started marching to Kazima. He could have probably taken the city with ease, but didn’t

want to be besieged by the heavily armored Sassanids, so his troops waited and rested to the south of Kazima, while Hormozd marched towards him. In the first days of April, the

tired Sassanid forces approached. The engagement that would occur in the area

is traditionally known as the battle of the Chains, due to the description of the Sassanid

forces in the Muslim sources: according to them the Sassanid infantrymen were chained

to each other to create a cohesive line, or to prevent any retreat, however, this makes

no sense tactically, as that would have made the infantry even less mobile, and each dead

warrior would have burdened their companions. We also never see this description in the

numerous battles fought between the Romans and the Sassanids. Most probably, this stems

from an incorrect reading of the Persian word “silsilah”, which can be translated as a mountain chain or a bounding chain or a single line of soldiers, so the word “chain”

might be a metaphor for the disciplined Sassanid infantry.

In any case, Khalid wasn’t going to allow Hormozd’s troops to rest, and his preparations

forced the Sassanids to form up directly to the west of Kazima at the end of the tiring march. Their formation was the traditional infantry center and cavalry wings. Meanwhile,

Khalid’s army was arranged in a similar manner, but for the time being stayed in the desert behind the hills dividing the two armies. This delay only added to the fatigue among

the Sassanids, as they had to stay in formation in their full panoply under the sun. However,

this waiting couldn’t continue for long, as the Sassanids controlled the springs in the area, so a few hours later Khalid emerged on the hills and his troops stopped some distance

away from those of Hormozd. The only surviving primary sources of this

engagement belong to the Muslim historians, so we will present their view of this battle.

As was customary for the region and traditional for the Roman, Sassanid and Arab battles of

the era, the battle started with a duel, as Hormozd moved forward and called Khalid to

fight him one on one. Apparently, Hormozd then dismounted and Khalid followed suit.

As two generals clashed and fought to a standstill, a few Sassanid skilled warriors attacked Khalid.

Another Arab general, Qaqa bin Amr, who will play a larger role in the future, saw this

and also decided to join the fray, attacking Khalid’s assailants. Qaqa and Khalid were

able to overcome the Sassanid fighters and killed Hormozd.

The Arab generals returned to their lines and Khalid ordered his troops forward. The

armies engaged each other. On the wings, the balance of forces didn’t allow either side

to gain the upper hand, while in the center the Muslim infantry charged their counterparts a few times, clashing and falling back without dealing much damage. However, the Muslim troops

were much more rested, as even the infantrymen had travelled to the battle mounted. The Sassanid

footmen weren’t able to rest after their march, and each charge tired them even more.

During one of the charges Khalid’s center managed to crack the disciplined Sassanid line in a few places. The Sassanid army, which was left leaderless

in the wake of the duel, panicked, and the commanders leading the wings - Qubaz and Anushjan

- started retreating with their horsemen. Their Muslim cavalry counterparts didn’t

chase the enemy horsemen and instead enveloped the Sassanid center. Soon, the battle was

over. We don’t have a clear source on the number of casualties, but it is probably fair

to assume that half of the Sassanid army was lost, while Khalid’s casualties were less than a few thousand. Meanwhile, shah Yazdegerd, who received Hormozd’s

letter in late March, decided to send an army under Karinz to reinforce his governor. The

speed at which it happened suggests that only the forces around the capital were gathered;

according to the sources, Karinz had somewhere between 15 and 25 thousand men when he moved

south and crossed the Tigris. He was apparently moving towards Uballa to

help the governor, but after he crossed the small river called Maqil, he encountered the rest of the Hormozd’s army led by Qubaz and Anushjan, some 10 thousand troops. Karinz

was told about the events of the battle of the Chains. Simultaneously a mobile force

commanded by Muthanna appeared nearby, probably sent by Khalid to chase the remainder of the

Sassanid force and scout ahead, while he was recruiting from the ranks of Arab tribes in

the area of Kazima and Hufeir. We don’t know what Karinz was thinking at

this point, but it is clear that the Sassanids understood that they were not dealing with a minor raid, and they faced a traditional Bedouin Arab army made up of light cavalry.

Catching Muthanna’s mobile force in the open field would be impossible, since the shah’s army was considerably slower, so Karinz didn’t move to the strategically

crucial Uballa to protect it, likely worried that Muthanna would be able to attack his flank and rear. The Sassanid general decided to sacrifice Uballa and keep his position

along the river in order to prevent Khalid from crossing the Tigris, and also from marching westwards to the most important city of the region – al-Hirah.

In the meantime, Khalid was informed by Muthanna that a new army was moving to the south. The

Battle of the River

Sassanid position left him no other way to advance. Using the whole army to take Uballa

might have entrapped him, so only a small group was sent to take it, while Khalid went on and united with Muthanna. The battle that is now known as the Battle

of the River took place in the third week of April. The Sassanids had anywhere from

25 to 50 thousand troops, depending on the sources, while Khalid commanded around 18

thousand, as he was able to reinforce his army by recruiting from the local Arab tribes.

The sources for this battle are conflicted, so we will try to do our best to form a coherent narrative. Before the armies formed up in the morning,

Khalid personally scouted the positions of Karinz’s forces, and was now sure that winning a set piece battle was his only option to continue the campaign. He returned and the

armies started to get into formation, both having a similar structure with infantry in the center and cavalry on the wings. The Sassanid army was deeper, as its commander made no

attempts to widen his front and outflank the enemy, probably relying on the superiority

of his troops and the fact that his second rank would be fresh when the time came.

The battle started with Karinz calling for a duel. According to the Sassanid sources,

the duels were a way for the commanders to prove to the troops that they are ready to fall for them, so a personal combat between champions was a usual sight. Khalid wanted

to answer the call, but one of the duelists who was near him galloped towards the Sassanid

commander and Khalid stayed back. In the ensuing duel, the Arab fighter was

able to defeat his opponent. That demoralized the Sassanids, so Qubaz and Anushjan were

probably forced to march forward and demand another duel, to restore their morale. The

Muslim wing commanders Asim and Adi galloped to them. Soon, the Sassanid commanders were

dead and Khalid ordered his entire army forward. Despite the fact that the Sassanids lost all

of their top commanders, initially this charge was fruitless, as the forces of the Caliphate

failed to make any headway and were even pushed back. But this push back made the Sassanid

lines disorganized, as the units lost cohesion due to the lack of command. Khalid was able

to exploit this, and his counter-attack created even more holes in the enemy formation. The

rear of the Sassanid army attempted to retreat, while the front was still fighting. However, left with no support, the front was soon massacred. Lightly equipped and fast Muslim troops were

able to catch up to the fleeing Sassanids with ease, and the battle restarted along the river. The sources do not give a clear picture of what happened here, but most of

the Sassanid losses occurred in that area, as some were killed, some drowned, and some were able to cross the river. By the end of the battle the Shah’s army lost anywhere

from 15 to 30 thousand troops, while Khalid’s casualties were in the hundreds.

After the victory at the Battle of the River, Khalid didn’t cross into central Iraq, probably

for a variety of reasons. Firstly, he needed to create a new administration in the region

and start collecting taxes. Secondly, moving into the Sassanid empire would have stretched

his supply lines and would have put him into territory with no Arab tribes. On top of that,

Khalid liked to fight on the edges of the deserts, which gave him the opportunity to outmaneuver his opponents when needed. The caliphate’s commander established a new

authority in the province, with its inhabitants starting to pay the Jizya tax. Simultaneously,

scouts from the local tribes were sent to the west and north to discover if the Sassanids had more armies nearby. As the Persian road and postal system were

probably among the best of their time, the shah learned about another defeat shortly after, and while Khalid was making his preparations, Yazdegerd ordered the troops from the northern

and eastern parts of the empire to march towards the capital, Ctesiphon. A direct attack on

the region controlled by Khalid was difficult, as the Arabs now controlled the crossings,

so when the first army, commanded by Andarzaghar, arrived, it was sent toward the city of Walaja,

the first strategic target on the road between Uballa and al-Hirah.

It was expected that the Arabs would attack in this direction, so the remnants of the Sassanid forces which fought under Karinz joined Andarzaghar, bringing his numbers to

somewhere between 25 and 30 thousand troops. This army took positions outside of Walaja

sometime in May. The second army was led by one of the top commanders in the Sassanid

army, Bahman, and it was supposed to reinforce Andarzaghar if the Muslims indeed decided

to move to al-Hirah. For now, this force of 20 thousand was to be stationed along the

Euphrates, halfway between Uballa and Walaja. Meanwhile, Khalid’s scouts, being from the

local tribes, were able to gather information with impunity, so he seemingly knew about

every enemy move. He decided that his smaller force needed to defeat one of the armies opposing

him, and he could not allow them to reinforce each other. So, he left a minor garrison around

Uballa and marched west, hoping to defeat Andarzaghar, without alerting Bahman.

Along the way, Khalid reinforced his army from the Arab tribes, which were now more eager to join his ranks, since the tax imposed by him was lower than the one, they had to

pay before, and that brought his numbers to around 15 to 20 thousand. The goal was to

destroy the army under Andarzaghar before Bahman could reinforced it. Although Bahman’s

army noticed the movement of the Arabs, they were much slower, so Khalid was able to reach Andarzaghar well before Bahman, sometime in the second half of May.

Battle of Walaja

According to the sources, Andarzaghar had enough room to maneuver and wait for Bahman along the river, but he was confident in his troops and kept his position. For almost a

day the two armies seemingly remained in their respective camps, within the reach of each other, without attempting to start a battle; the Arabs were probably resting after their

forced march, and the Sassanids were hoping that this wait meant that they might be reinforced.

However, this wait couldn’t last, since Khalid knew that he had to score the decisive

victory before the second Sassanid army arrived, so on the next day both forces formed up in

standard formation with a center and two wings. The battlefield near Walaja was an even plain

stretching between two low, flat ridges which were about 1 kilometer away from each other.

To the north east was a barren desert, with the river Khasif running close to the eastern ridge. Both armies had the ridges behind them, meaning that an attack from the rear was not

possible to begin with. The Sassanid leader was surprised to see that

the whole Muslim army was smaller than previously reported, and that it only consisted of footmen,

which contradicted what he had heard about the crucial role Khalid’s cavalry played in the previous battles. Despite that, he was convinced that his position was impenetrable

and decided to wait, as both armies knew that Bahman couldn’t be too far away.

Indeed the Muslim commander ordered his entire army forward. Led by Khalid, who fought in

the front rank, the army of the Caliphate charged into the enemy. For an hour or so,

the two lines fought to a standstill, losing few warriors. But the Sassanids had the numbers,

so their tired front line was replaced by the rear rank, which gave them edge. Despite

Khalid’s personal martial skill, his troops were getting tired, so Andarzaghar’s counter-attack

started to push the Muslim troops back. Slowly but surely the Sassanids advanced, while the

Arabs were getting dangerously close to the ridge, which would have made any retreat impossible.

At this point, Khalid gave a signal that changed the course of battle: the cavalry that he

sent into the desert during the previous night appeared on the eastern ridge behind the Sassanid

army. This was Khalid’s trademark move, as his mobile cavalry was able to hide in

the deserts with ease. The advance of the Sassanid army away from its fortified position

meant that its rear was undefended. The light Arab horsemen charged into the Sassanid

lines, while Khalid’s infantry lengthened its front to envelope the wings of Andarzaghar’s

army. Minutes later the battle of Walaja was over. The Sassanid commander was dead and

his army was completely destroyed, with only 5 thousand survivors managing to retreat from

the field. Khalid’s casualties were around 3 thousand.

As Khalid’s troops were tired after the long march and the battle, his army wasn’t able to pursue the Sassanid survivors. Those were mostly the Christian Arabs who were more

mobile, and they managed to find shelter in nearby Ullais. The messengers from this group

went to other Christian Arab tribes to the northwest, asking for help, and also informed

the shah in Ctesiphon. The tribes answered the call of their kin, while Yazdegerd sent

messengers to Bahman to go towards Ullais. It is not clear why, as Arab and Persian sources

are conflicted, but according to the former, Bahman gave command over his army to another

general called Jaban, who marched with the entire army to where the Christian Arabs were

concentrating. The Persian sources claim that Bahman returned to Ctesiphon with his entire

army. Meanwhile, Khalid moved his troops towards

the city, and sometime in May fought the allied Christian Arab and Sassanid army near Ullais.

The details of the battle are lost, but we know that the Muslims won. The sources are

once again conflicted on the number of casualties, with the Arab sources stating that Khalid’s

force killed 70 thousand enemies, mostly through the executions after the battle, while the

Persian writers think that the army facing Khalid’s 18 thousand was comparable in size

and managed to retreat towards al-Hirah after a minor defeat.

In any case, in the last days of May Khalid approached al-Hirah, which was the initial

goal of his campaign. Again, the sources are inconclusive. We know that the local Sassanid

garrison and their Arab allies mounted resistance for a few days, but eventually, the sides

decided to negotiate. As Khalid promised to spare the lives of the population in exchange

for the payment of the Jizya tax, the locals decided to surrender.

Battle of Muzayyah

The Arab commander spent the next few months building up a new administration in the region and collecting taxes. At the same time, raiding parties were sent to Central Iraq and towards

the border of the Eastern Roman Empire, and this raiding brought both loot and information

on enemy movement. Some sources claim that the Caliphate gained a degree of control over

Central Iraq, but it seems that Khalid didn’t have enough troops to keep such a wide region

under his authority. Still, the Caliphate’s raiding parties were

not getting much resistance to the north and northeast, while his scouts informed him that

the Sassanid garrisons to the northwest were still intact, with larger concentrations at

Anbar and Ain-al-Tamur. The first one was further away and the direct route to it was

through Ain-al-Tamur, but attacking the fort of Anbar would have been more unexpected so,

in late June of 633 Khalid left half of his troops in al-Hirah and marched west towards

Anbar with a 10 thousand strong army. Anbar would become the first Arab attack across

the Euphrates river. The details of the engagement that happened here are unclear, but it seems

that Khalid’s decision to attack Anbar surprised his opponents, and the leader of the garrison,

Sheerzad, was forced to surrender after the Arab archers showed their effectiveness.

Then the Caliphate’s raiding parties approached the town of Ain-al-Tamur from the direction of al-Hirah, so when Khalid engaged the Sassanid troops, mostly made up of Christian Arabs

from the west, in July, he was able to win with relative ease. The leader of the Christian

Arabs was taken prisoner and then executed, and the city surrendered to the Muslims.

Events of the next few months between July and September are shrouded in mystery, as some sources claim that Khalid was staying in Anbar and Ain-al-Tamur, slowly setting

up the administration of the newly acquired region, which seems uncharacteristically passive

for him. Others claim that the last 2 remnants of the apostate activity of the Ridda Wars

were to the south, so Khalid moved most of his non-garrisoned troops towards Dawmat al-Jandal,

and helped his fellow Caliphate general, Iyad ibn Ghanm, defeat the rebels in the region.

This inactivity or absence gave some time to the Sassanids, and they started recruiting and concentrating 5 armies in the area between Muzayyah and Husaid. Qaqa bin Amr, who was

left to command the garrison at al-Hirah, ordered the raiding parties in central Iraq and the garrisons of Anbar and Ain-Al-Tamur to take positions to the south of the Sassanid

forces, delay them as much as possible, and not allow these 4 small armies to unite into

one force. At the end of September Khalid returned to

al-Hirah alongside the troops he picked up around Dawmat al-Jandal, and ordered the Qaqa

bin Amr and Abu Laila to lead portions of the garrison to Husaid and Khanafis respectively

and take command, while his troops rested in the city. Apparently small Muslim and Sassanid

armies fought minor battles in October, and the Sassanids suffered minor defeats, which

compelled them to retreat towards Muzayyah. Khalid now had an open route to the Sassanid

capital Ctesiphon, but the Sassanid army at Muzayyah, and the concentrations of the Christian

Arabs in the area between Saniyy and Zumail, were still a threat, so the Caliphate commander

decided against attacking Ctesiphon. The main Sassanid army at Muzayyah probably considered

its position to be safe since it would be difficult to attack them without going through Saniyy and Zumail. At the same time, Khalid knew that attacking

the majority light cavalry Arab Christians could push them to the north to unite with

the troops at Muzayyah, so Khalid devised a plan. His army was already divided into

three corps and they moved directly against the Persians using the desert to avoid Saniyy

and Zumail. This was technically very difficult, as all three corps had to not only bypass

the enemy armies without being detected, but also arrive at the decided location simultaneously.

It was risky, but the possible reward was also high.

Everything worked as planned. Khalid’s corps converged on the target at the same time,

and during one of the nights in the first week of November, his 20 thousand attacked the sleeping Sassanid army of comparable size. The latter was not expecting this attack and

the army of the Caliphate scored an easy victory, killing more than 10 thousand Sassanid warriors.

After that defeating a smaller Christian Arab force seemed easy, but instead of confronting

them head-on, Khalid repeated his 3-pronged maneuver, to avoid the losses. The Muslims

suffered minimal losses, while the Christian Arabs lost more than half of their army. Apparently,

a few recent Muslim converts were among the killed, and their families sent an appeal

to the Caliph Abu Bakr to punish Khalid. This rejected appeal was sent through the future

Caliph Umar, and will become important for our story down the line.

Khalid’s mobility and the inability of his opponents to consolidate their forces meant

that the region between Muzayyah and al-Hirah was now under the control of the Caliphate.

We have sparse information on the early administration of these lands. The Muslim sources claim that

while the Persians living in the cities were often taken captive and enslaved, the local Arab population was forced to pay the Jizya tax, but was otherwise allowed a degree of

autonomy and even freedom of worship. More raids were sent across the Euphrates

in the next month, while Khalid was contemplating what his next move should be. Attacking Ctesiphon

was still dangerous, as that would have stretched the supply lines too much. That made an attack

on the only Sassanid target in the area - the city of Firaz - the only option. Firaz was

right on the border of the Sassanid and Eastern Roman empires. Khalid and his 20 thousand

reached the area in December. Once again, the sources are conflicted, but

Battle of Firaz

a few details that have reached our times allow us to form a coherent timeline. We know

that the local Sassanid and Roman garrisons united their strength on the north side of

the Euphrates, while Khalid held the crossing on the other side. Despite the fact that the

Muslim sources state that the united Roman-Sassanid force was large, it is fair to assume that

neither empire could have a large force in the area, since the Sassanids needed these troops in central Iraq, while the Romans were concentrating their forces on the crucial

coastal areas and urban centers already being raided by the smaller Muslim armies. Even

with a united force and the inclusion of the local Arab tribes, the allies led by the Sassanid

commander, Hormozd Jadhuyih, probably had between 15 and 25 thousand troops.

For 5 or 6 weeks the armies remained opposite each other, as neither side had a safe place

to cross the river. It seems that sometime in the third week of January, Khalid slightly

retreated from the positions he held, perhaps baiting his counterpart into attacking. Indeed,

the allied force crossed the river and formed up against the Muslims.

Both sides had a similar disposition with infantry in the center and cavalry on the wings. The allied army charged the Muslims, probably hopeful that their heavier equipment

would give them an advantage. Slowly but surely, this charge pushed Khalid’s lines back.

Simultaneously, the Muslim general ordered the cavalry units from the second rank to leave the main body and take position to the far left.

The Roman-Sassanid army continued to advance and the Muslims retreated even further. Khalid’s

detached force was ordered to take the bridge and then attack the allies from the rear.

This maneuver was successful, as Hormozd Jadhuyih’s army immediately started losing cohesion - the

allies thought that there was another big Muslim army that took the bridge, and would soon surround them. Simultaneously, Khalid’s main force started

their counter-attack, and those units of the allied army not killed on the spot started

routing towards the northeast. A certain number managed to swim across the river, but more

than half of the allied army was killed. Khalid lost a few hundred from his ranks.

Khalid was about to attack deeper into Persian territory, but he soon after received a letter

from the Caliph, Abu Bakr. The letter ordered him to cease his attacks on the Sassanids

and to move into Syria to battle the Romans. So, Khalid and a small contingent of his army

prepared to move west. As with the Mesopotamian invasions, there had probably been no better

opportunity for a strike into Roman lands, as the destructive quarter-century long conflict

from 602 to 628 had undermined crucial defences in both regions. The Roman east, with all

its religious, cultural, financial and strategic significance, was now dangerously vulnerable.

During 633, the Muslims sent four separate corps to invade Palestine, in addition to

the areas around the Sea of Galilee, the River Jordan and the Dead Sea. Though they achieved

success, assaults on the large urban settlements of the region could not be considered until reinforcements were brought up. So, both for the additional troops and for Khalid’s expertise

in warfare, Abu Bakr sent the order for him to move west.

To save time and to bypass Roman defences, the Muslim general chose a more dangerous

route through an especially desolate, waterless stretch of the Syrian desert, much to the

alarm of his sub-commanders. In order to survive, it is reported that Khalid, in his ingenuitive

way, ordered 20 camels be forced to drink large amounts of water so that they could

be used as makeshift storage tanks. The beasts were then periodically slaughtered along the

journey when nourishment was needed, and the water was then harvested from the camels.

After five grueling days of marching through this desolate landscape, the 9,000 strong

Muslim army emerged at Suwa. Then, they swiftly inflicted a minor defeat on the Roman Arab

clients - the Ghassanids - at Marj al-Rahit, while they were celebrating easter. Proving

his strategy correct, Khalid’s improbable desert crossing had also neutralised the Byzantine

defences on the Arabian border. Now he turned south, towards the Syrian town

of Bosra, where the arrival of his reinforcements led to its capture by mid-July of 634. Despite

this success, the Muslims had little time to celebrate. Roman Emperor Heraclius, who

was now in Emesa, sent his brother Theodore, and an Armenian general named Wardan, south

towards Ajnadayn, 25 miles southeast of Jerusalem, where they began to gather a large army. Spies

reported this gathering force to the Muslims, and the burgeoning Caliphate’s army marched

to meet their Byzantine opponents. Very few hard facts are known about this battle,

Battle of Ajnadayn

but we can reconstruct a version of the fight using the available sources. Muslim accounts

vastly exaggerate the number of Roman troops they faced, and it is likely even that the

weakened Byzantine forces in Syria - 10,000 strong and commanded by Wardan and Theodore

- were outnumbered by the 15,000 Muslims. Both armies formed up in extended lines with

their camps to the rear, and both sides stood ready with three divisions of infantry - right,

left and centre - while each wing had a cavalry flank guard. Behind the Muslim centre was

a small reserve, and in front of their centre was a small group of champions.

Before the battle began, a Christian bishop rode over to Khalid’s army and attempted to negotiate a Muslim withdrawal. However, the Rashidun general simply responded by offering

the traditional choice - conversion to Islam, payment of the Jizya tax, or death in battle.

The fighting at Ajnadayn began when the Byzantine auxiliary missile units, stationed ahead of

the main line, began to rain arrows and stones on their adversaries. As the superior Byzantine

ranged units loosed, the Muslims suffered losses and were unable to respond. However,

one Muslim warrior named Dhiraar, heavily armoured and brandishing a heavy shield stolen

from a Roman soldier, marched directly into the arrow fire, shouting his war cry. After

the hail of missiles ceased, Dhiraar and his entourage of fellow champions were met by their Byzantine counterparts, and it is said the Muslims got the better of the fighting,

slaying several Roman elite warriors and two generals.

As the dueling came to an end, the Rashidun army attacked, and the subsequent fighting was a slogging match with little maneuver, and lasted until nightfall. The next day,

Byzantine commander Wardan attempted to lure Khalid into a trap by offering a parley, but

the plan went wrong and he was instead killed by the fearsome Dhiraar.

Aiming to exploit the confusion which this loss of leadership caused in the Roman ranks,

the Arabs attacked again with their flanks in front and centre behind. After savage hand

to hand fighting, which exhausted and depleted both armies, Khalid deployed his 4,000 strong

reserve in the centre and drove deep wedges through the Roman formations in this area.

Unable to withstand the pressure any further, their line collapsed.

After this defeat, Emperor Heraclius sent his brother Theodore back to Constantinople

in disgrace. At the same time, the remnants of his shattered army, in addition to the

local Roman population, withdrew to the apparent safety of the walled cities, which subsequently

became crowded with refugees. Perhaps an omen of things to come, Heraclius then retreated

with his headquarters further north, to the city of Antioch, due to the fact that Muslim forces now controlled the countryside and were expected to advance on the most prominent

urban centre in the area. A week after their victory at Ajnadayn, the

Arab forces began to march north in the direction of Damascus. On their way, they had to leave

a mounted detachment at the city of Fahl, ancient Pella, to keep the Roman garrison

there tied down while the main army marched onward. After this was done, the Muslims reached

Yaqusa on the southern bank of the Yarmouk River. Here he was opposed by a blocking force

of Byzantine troops on the northern shore. They were in no real position to offer serious

permanent resistance, but they were there to delay the Muslims, and to allow the great city to further prepare for a coming siege. After a short battle here and another battle

against 12,000 Romans at the Yellow Meadow - otherwise known as Marj-us-Suffar - the

road was clear to Damascus. When the invading Arabs neared the city, the

Siege of Damascus

Muslim commander realised that his forces were not numerous enough to encircle it entirely.

Instead, each of the Muslim sub-commanders stationed their contingents outside of the

city’s various gates, fully blockading the crucial thoroughfares by August 21st, with

a total of around 20,000 soldiers - 16,000 infantry and 4,000 ‘mobile guard’ cavalry.

Damascus immediately began starving due to the lack of supplies and unpreparedness for

a siege, while the Muslims were well supplied due to their domination of the fertile and

productive local countryside. As the swift Arab light horsemen were relatively

usel ess in a siege, Khalid Ibn al-Walid sent a few hundred of them to the Eagle’s Pass

to the north, in order to act as scouts. Here, they watched for any Byzantine relief force

aiming to pass through this choke point. The other half stayed near the city as a reserve,

ready to help repel any sortie made by the Romans.

In Antioch, the Roman Emperor learned of the siege and sent a 12,000 strong relief force,

along with plentiful supplies, to help Damascus on September 9th. When this force reached

the narrow pass where the Muslim scouts were stationed, it pushed the cavalry back. One

of these scouts managed to send notice to al-Walid and he, gambling that repelling the

relief attempt was more important than maintaining too tight a blockade, took the remaining cavalry

at night to the Eagle Pass, where he managed to rout the Romans. Despite their apparent

success, the besieging Arab forces were now stretched thin by Khalid’s withdrawal. Historians

believe that if the garrison’s general Thomas had chosen to launch a sortie at this point,

the Byzantines could have broken the siege, but they did not and therefore lost the opportunity.

It seems that al-Walid realised he had put the siege in danger with his gamble and he hurriedly returned to Damascus after he attained victory at the Eagle’s Pass.

As the garrison and Thomas realised that no relief was coming, morale among the defenders

of Damascus became weaker and weaker; it was clear action would be needed. So, the Emperor’s

son in law decided to launch a counteroffensive of his own. For this first attack, Thomas

decided to concentrate on one specific section of the city, drawing men together from all

sectors of the city towards the Gate of Thomas, where he was faced by around 5,000 soldiers

under Shurahbil. After the defending soldiers gathered in the

area, the Byzantine commander began his sortie by ordering his archers to rain down a constant

stream of arrows against their enemy, to which the Arabs responded accordingly. Using the

cover granted by the Roman missile units, the infantry rushed through the Gate of Thomas and fanned out into battle formation, with Thomas himself leading the assault. During

the subsequent skirmish, it is reported that Thomas both broke through a section of the Muslim line and almost killed Shurahbil, but he was then shot in the eye by the widow of

a slain Arab soldier. Despite some level of success, the sortie had failed to break the

siege and the Byzantine forces retreated into the city. As they did, it is said that the

injured Roman leader swore to take a thousand eyes in return for his own.

That night, another plan to break the siege was devised by the defenders. As a concentrated

attack on one of the gates had failed, Thomas would this time launch simultaneous strikes

from four of the gates. Two large forces were gathered at the eastern gate, where Khalid

was in command, and at the Gate of Thomas, where the main attack against exhausted enemy units would be undertaken. The other forces at the Small Gate and the Jabiyah Gate were

designed to pin their besiegers in place. As Thomas sounded the attack, a grinding battle

took place at the Jabiyah gate, with both sides suffering many losses. After a while

of this slaughter, Abu Ubaidah and his forces at this gate managed to doggedly repulse the

Byzantine assault, driving them back into the city.

The situation was far more serious at the Eastern gate, where the Byzantines had a larger

force. This larger contingent of defenders managed to break the Arab infantry and drive

them back, but Khalid himself then arrived with 400 elite mobile guard cavalry, and with

them, struck the Roman flank. This weakened the sortie irreversibly and the defenders

were slowly driven back inside the gates. Once again however, the worst of the fighting

once again occurred at the Gate of Thomas. Here, the Byzantine forces were led by the one-eyed Thomas himself and, after intense fighting, there was still no weakness in the

Muslim ranks. At this point, the Roman commander seems to have realised there was no point

in continuing the grinding melee, and commanded a slow, steady withdrawal. All the while,

the Arab archers continuously showered his men with arrows. This was the last effort

by Thomas to break the Muslim siege, and it had failed with the loss of thousands of men.

With this defeat, he could no longer afford any more attempts at a breakout.

A Greek in Damascus known as ‘Jonah the Lover’, in Arab sources, climbed over the

wall and informed Khalid that on the night of the 18th of September, there would be a Christian religious ceremony which would leave the walls relatively unguarded. He supposedly

betrayed his city because his marriage to his fiancee had been interrupted by the siege

and, frustrated, asked for the Muslims’ help in obtaining said bride. This man soon

converted to Islam, but the details are incredibly vague.

Whatever the case, details of the opportunity led Khalid to borrow ladders from a local

monastery and to purchase ropes in order to form an assault party. That night, a 100 strong

contingent, led by the Muslim general himself, climbed the walls, dropped into the city and

killed the guards at the Eastern Gate. Then the attackers flung open the gate and let

the remainder of Muslim forces at the Eastern Gate inside the city. The other Byzantine

detachments stationed elsewhere were unaware of this surprising development and, instead

of helping, stayed at their posts. At the same time, Khalid began to fight his

way toward the centre of the city. Now attempting to save the city for a final time, Thomas

sent envoys to Abu Ubaidah at the western Jabiya gate offering surrender and a payment

of Jizya in exchange for a capitulation by terms. This was given by the supposedly peace-loving

Abu Ubaidah. However, Khalid, who had finished slaughtering his way to the centre of the

city, was furious that a surrender had been allowed even though the city had technically been taken by storm. Nevertheless, the many Muslim unit commanders agreed that a surrender

would be honoured - Khalid reluctantly accepted this judgement.

The fall of Damascus was a shock for the Byzantines, as they probably thought that the Muslim attack

on the region was a massive raid and not a full-on invasion. Syria and Egypt were the

most important provinces of the empire, and the fall of the former would mean that the

land route to the latter was cut, and it was now also vulnerable to being occupied. Emperor

Heraclius’ couldn’t allow that, so he started sending orders to the provinces in order to bring in more reinforcements to the region.

Battle of Maraj-al-Debaj

Simultaneously, the political situation in the caliphate had also changed, as caliph

Abu Bakr passed away in late August of that year, and was replaced by Umar. The new caliph

immediately started implementing administrational and military reforms, creating new administrative

positions in the provinces, and changing the formation of the army from the one created on the tribal principle to a more centralized one. Immediately after his ascension, Umar

sent a letter to the army, reliving Khalid of his post and appointing Abu Ubaidah in

his place. We don’t know if this was part of the reforms or, as some sources claim,

it happened due to the previous animosity between the new caliph and the general.

In any case, it seems that before the messengers could reach Damascus, the 3 day-peace the

Muslims promised Thomas had passed, and Khalid, alongside 5 thousand cavalry, guided by Jonah,

started pursuing the Romans. Thomas had around 10 thousand people with him, both soldiers

and citizens of Damascus, but instead of finding refuge in one of the nearby towns, this group

was heading towards Antioch, and that allowed the Arab cavalry to catch up to them to the

south of Latakia sometime in late September. The details of the engagement now known as

the battle of Maraj-al-Debaj are scarce, but according to the Muslim sources, a cavalry

detachment of a few hundred caught up and took position to the south of Thomas. The

Romans immediately noticed them, deciding that they would be able to defeat this small group with ease. To the surprise of the Romans, as soon as the Arab cavalry and Roman infantry

started fighting, another group of Khalid’s horsemen appeared to the east. Although the

Romans had thousands of refugees in their midst, they still outnumbered the Muslims, and a portion of their infantry formed up to face the new threat.

However, a half hour after the battle was joined here, a third group of Arab cavalry

started charging from the north, and the Romans barely got into a defensive formation in time

to prevent it from breaking through. Thomas’ situation was becoming dangerous, as the route

to Damascus was now cut off, but the Romans were still fighting on an equal footing, and

the battle raged on three sides. An hour later Khalid himself appeared to the

west with the largest part of his army and charged the Romans. Despite the fact that

Thomas managed to get a few units to this front, they were swept aside almost immediately,

and the Arab cavalry was now deep inside the Roman formation. Thomas was soon killed. The

Roman resistance continued for some time, but was broken within an hour. Some soldiers

and refugees were able to slip away to the north, but the majority of the Romans were either killed or captured. Khalid lost just a few hundred troops.

Immediately afterwards, the Arabs headed to Damascus and reached it in early October.

Apparently, Abu Ubaidah already received the messenger from the caliph, and informed Khalid

of his demotion. According to sources, the latter accepted it without much protest, but

it did change the flow of the Caliphate’s expansion in the region . Abu Ubaidah was

much slower and more deliberate than Khalid. Umar preferred a more hands-on approach to

the armies, often issuing orders after every engagement, which slowed down the campaigns

due to the distance to Medina. He even placed informers in the army, which made Abu Ubaidah

even more careful in his decisions. At the same time, the Muslims received some reinforcements,

bringing the total number of their troops to 30 thousand. However, that wasn’t the only change in command made by Umar, which brings us back

to Iraq, where Khalid left Muthanna in charge of a 9-thousand-strong army in 634. For the

next few months Muthanna, whose numbers weren’t enough to conquer any more lands, implemented

the tactic of raids in order to keep the superior Sassanid forces at bay. The details are lost

to time, but the Sassanids, who were used to fighting in pitched battles, were having a difficult time containing the raids, and one of them even reached Babylon.

The best Sassanid commander, Rostam, who basically controlled the court of the 10-year-old shah

Yezdegerd, was reluctant to leave the capital, worried that it might incite another revolt.

But Muthanna’s raids were too dangerous, so the general decided to take command over

the forces in Iraq and marched south, supported by the Sassanid generals Bahman, Jaban and

Narsi, and the Armenian noble Jalinus . Even before this multipronged counterattack

began, Muthanna knew that he needed reinforcements, and sent a messenger to the capital. By August

this messenger was in Medina, just in time for the ascension of Umar. The new caliph

appointed Abu Ubaid, not to be confused with Abu Ubaidah, to command in Iraq, and gave

him 6 thousand or so troops to reinforce Muthanna. The latter was now informed of the Sassanid

counterattack, and when Jaban got close to al-Hirah in late September, the Arab commander abandoned it, retreating to Khaffan . By early October Abu Ubaid joined him, bringing the

total strength of the Caliphate’s force to more than 15 thousand, a similar number to that commanded by Jaban, who crossed the Euphrates and was now at Namariq. The details

of the battle of Namariq are not clear, but it seems that Jaban suffered a minor defeat

and was forced to retreat beyond the river. Abu Ubaid decided to fight the approaching

Sassanid armies in detail, and marched north towards Kaskar, hoping to defeat the smaller

army under Narsi and knock him out. Although the Muslims won again, the Persian army managed

to retreat mostly intact, and Abu Ubaid, who knew that Jalinus might cut his retreat to

al-Hirah, moved his army double-time to prevent this from happening. Indeed, the army of the

Caliphate reached the city before Jalinus blocked them. The closest Sassanid armies to al-Hirah were those of Jalinus and Bahman. A letter from Rostam ordered them to unite

their troops, cross the Euphrates and attack the city.

Battle of the Bridge

In late October of 634 their united armies, numbering around 20 thousand, attempted to

force the river near Kufa, but Abu Ubayd and his 15 thousand were able to halt this crossing.

For some time, the armies stood in front of each other screaming insults, until a Sassanid

emissary approached Abu Ubayd with Bahman’s message: “Either you cross over to our side,

and we shall let you, or we shall cross over to your side, and you must let us!"

Although his officers protested it, Abu Ubayd was eager to cross and fight in a pitched

battle, so he ordered his army to do that. Seeing this, Bahman repositioned his troops

slightly to the north, allowing the Muslims to move across and form up. Unlike previous

battles, the Persians had a dozen or so elephants, and they were placed in the vanguard with heavy cavalry between them and the infantry in the second echelon. Abu Ubayd’s army

crossed the river in 2 hours and started to get into formation, once again with horsemen in front and the footmen in the second line. Bahman continued to wait, and it was Abu Ubayd

who gave the order to his soldiers to attack. The Arab cavalry galloped forward, but their

horses were scared of the elephants, probably seeing them for the first time, and the charge

stopped before it managed to reach the Sassanid lines. In response Bahman moved his archers

to the front and commanded them to shoot at the retreating Arabs. The volleys killed and

wounded many, and when the leaders of the army of the caliphate attempted to move their archers forward to start skirmishing, the whole Arab line became chaotic and disjointed.

The Persian commander used that and directed his cavalry and elephants to attack. While

the cavalry was mostly stopped, the elephants easily created wedges everywhere they struck.

The Arab army was slowly, but surely forced back. The presence of the elephants was panicking

the horses, so in order to stabilize the front, Abu Ubayd commanded his horsemen to dismount.

He led a group of warriors himself, killing a few elephants and their entourages. However,

another elephant was sent towards the Arab leader and soon he was killed by the beast.

Many other Muslim leaders were killed and their army started fleeing in chaos, and the Sassanids started chasing them. Muthanna was one of the last remaining commanders, and

he achieved some degree of discipline and organization at the crossing, leading the rearguard and allowing the remainder of the army to retreat. He was badly wounded during

the fight, but his actions saved thousands. The battle of the Bridge was the first battle

the Persians won in this war. More than 10 thousand Muslims lay dead, while the Sassanid

casualties were around 2 thousand. Over the following weeks, Bahman didn’t

pursue Muthanna, who withdrew to Ullais, and returned to Ctesiphon. Some sources claim

that there was another rebellion against Rostam, others that Bahman was sent to deal with the

Turkic raiders. The sources are also conflicted on the events that happened in Iraq later

in 634 and then in 635, with some chronicles asserting that Muthanna’s army deserted

and he abandoned all the previous conquests, and others stating that the Sassanids sent

a large army under Mihran, and it was decisively defeated at Buwaib in April of 635. In any

case, this lull in action allows us to return to the Levant.

Battle of Pella

The Muslim army was getting used to the new command structure, and using this pause, Heraclius

was bringing more forces to the region, by land to Antioch and, as the Romans had complete

naval control, by sea to the various ports. The second group was to be commanded by Theodore

Trithyrius, the treasurer of the Empire, and in December of 634 it started assembling to

the west of Pella, which was the perfect place to launch an eastward attack, cutting the

line of communications with Arabia. It is not clear how big this army was . Spies had

informed Abu Ubaidah about this threat in December, and in early January of 635 he marched

south towards Pella, leaving a corps under Yazeed behind.

As soon as the small garrison of Pella learned of this, it retreated towards the main army, flooding the river Jordan and creating a swamp-like territory dividing the Byzantine and Arab

armies . After occupying Pella, the Arab army commanders decided to move towards Baisan

to engage Theodore. They didn’t know the terrain of this area well , so soon after

the vanguard led by Khalid got stuck in the mud, and the Muslims were forced to withdraw

back to Pella . Theodore waited for a week or so, hoping that

his foes would become less vigilant. On the 23rd of January he marched his troops towards

the river with a plan to attack the Muslim camp at night. However, the Muslims had placed

scout troops along the river, so as soon as the Romans started crossing, the Arab camp was informed of it and started to form up for battle.

We have only limited details on the battle, which, according to the Arab sources, raged

through the night and most of the next day. The Romans were able to push their counterparts

back to the camp using their slightly larger numbers. According to one chronicle, Theodore

was wounded in one of the charges, and the resultant loss of morale made the Romans retreat.

When they began crossing a marsh, the Arabs used this to their advantage: they attacked,

killing thousands. The rest returned to Baisan. Whatever was left of the Roman army dispersed

into various garrisons to the west and south, while Theodore returned to Antioch by sea.

There was no army to fight back against Abu Ubaidah, so he divided his army into corps

to conquer as many cities as possible. Shurahbil took Baisan and then Tiberias. Afterwards

Shurahbil and Amr bin Al Aas went south, while Abu Ubaidah and Khalid marched north. By the

March of 635 the Muslims were in control of the while region to the south of Beirut, save

for Caesarea, which withstood a siege reinforced by Heraclius, and Jerusalem, which had the

strongest fortifications . Heraclius probably thought that the Muslims

will be busy with the sieges and he has some time, so he was busy recruiting in order to counter-attack in 636. Simultaneously the alliance with Yezdegerd was established Heraclius

married his granddaughter to the young Sassanid shah. It was planned that the Persians will

attack the Muslim positions from the east. Meanwhile, Abu Ubaidah’s 15 thousand were

moving north and by November took over the territory between Damascus and Emesa, putting

this major city in danger. Heraclius rushed reinforcements, which brought the strength

commanded of the garrison commanded by Harbees to 8 thousand. In early December the city

was besieged. Harbees hoped that the Arabs, who weren’t

Siege of Emesa

used to the cold will not be able to sustain the siege for too long. At the same time,

Emesa was a well-fortified city, with the walls 1 mile in diameter and a moat surrounding

it and a citadel within the walls, so the defenders’ situation wasn’t hopeless.

The Muslims weren’t strong at the art of siegecraft at that point and the lack of siege weapons made the assault impossible. So, for weeks and then months the sides did nothing

but exchange arrow volleys. By March of 636 winter began to subside, and

it was becoming clear that the Arab army is planning to starve the Emesans. The food supplies

were getting dangerously low, so Harbees decided to sally out and kill as many foes as possible,

believing that it might end the siege. He left small units to defend the walls and concentrated

more than 5 thousand near the southern gates. Initially this sortie was very successful

– the Muslims were caught unprepared and were outnumbered 2-to-1, which led to hundreds

of casualties and forced them to retreat under Harbees’ pressure. However, Khalid managed

to get his cavalry together, arriving to the area of battle shortly after. The numbers

were now on the Arab side, and this was enough for the Romans to break off the fight and return to the safety of the walls. The defenders were jubilant and not at all

surprised when the Muslim army gathered to the south and started withdrawing. Harbees

decided that he can score a brilliant victory and immediately marched out of the city with the same 5 thousand. He caught up to the retreating Muslims a few miles to the south, but as soon

as his mounted troops started charging, Abu Ubaidah’s units turned back and attacked.

Few minutes later the Romans were surrounded from all sides. Harbees was killed and only

a few hundred of his soldiers escaped. After the short battle, the Arabs returned to the

city and the garrison which was left leaderless surrendered. Meanwhile, to the north, Emperor Heraclius has been preparing an army to counter-attack

for some time. Various sources provide numbers of this army ranging from a very modest 30

thousand to the fantastical 400 thousand. It should be noted that the chroniclers who

wrote on this war lived at least one or two generations after the events, so their depictions

weren’t based on first or even secondhand accounts. We know that at the peak of the

Byzantine-Sassanid War of 602-628, Heraclius was able to raise an army of 70 thousand for

his attack on the Sassanid empire, but that army had a considerable Göktürk element.

At the same, the Byzantines had to keep some forces in Italy, Balkans and the Caucasus

in order to check the encroaching Lombards, Slavs, Avars, and Khazars. In our opinion,

the Byzantines outnumbered their opponents at least 2 to 1, but considering the logistical

situation in the area of operation, their numbers were below 100 thousand.

Heraclius, who was now in his 60s, suffered from edema, so he wasn’t going to lead the

army, predominantly made of Greeks, Armenians and Christian Arabs, personally. Instead,

the army was divided into 5 columns, commanded by 5 generals . The plan was to engage and

surround the Muslim forces around Emesa, and use another column to take Damascus and prevent

the troops of the Caliphate operating to the south from reinforcing the northern group . The army left Antioch in the middle of June.

Unfortunately for the Romans, a few days before their leading column reached Emesa, the Arabs

learned about the counter-attack, either from their spies or from the prisoners they took while raiding Shaizar , so Abu Ubaidah ordered his corps to fall back. Initially, the idea

was to retreat to Damascus to preserve this conquest, but the city was surrounded by open

space that would have given an army with superior numbers an advantage, so the Arabs started

retreating towards Jabiya, which was located between the river Yarmouk to the south, lake

Tiberias to the west, and the desert to the east. Messengers were sent to the southern

group with the order to march towards Jabiya. The Byzantines, who barely missed an opportunity

to crush their opponent around Emesa, started chasing the Arabs, slowly coalescing after

taking the city. They retook Damascus and continued south, and sometime in the middle

of July 636, their vanguard made contact with the Caliphate’s rearguard to the north of

Jabiya. The Arab commanders, who initially liked their position, now understood that they might be attacked from the southwest – via the narrow

passage between lake Tiberias and the river Yarmouk. The Byzantine field army could have

engaged them from the front, while the garrison of Caesarea might have attacked using the passage. Therefore, Abu Ubaidah left Khalid in command of the rearguard and started repositioning

his troops. The latter engaged the Byzantine vanguard, led by the light Christian Arab

horsemen, allowing the rest of the army to move unharassed.

Battle of Yarmouk

The Muslims encamped in the eastern part of the Plain of Yarmouk. Some distance to the

east of them were the lava hills stretching from north to east of Azra, and the mountains

of Jabal-ad-Druz. A few days later, probably in the last days of July, the Roman army entered

the plain and built a fortified camp in its western part.

With the central portion of the plain left unoccupied, the armies started preparing for battle by scouting the enemy positions. The sources mention extensive negotiations which

continued for weeks, but the details of the talks are convoluted. In short, they ended

in failure and the battle was inevitable. According to some sources, the caliph’s

reinforcements, consisting of 5 thousand famous Yemeni archers and a thousand footmen, who were veterans of the earliest Muslim campaigns in Arabia, joined the army sometime during

this negotiation. The battlefield was enclosed on its western

and southern sides by deep ravines. To the west, Wadi-ur-Raqqad flowed into the Yarmouk

River near Yaqusa. This stream ran north-east to south-west for 11 miles through a deep

ravine with very steep banks. The ravine was crossable at a few places, but there was only

one main crossing, where the village of Kafir-ul-Ma stands today. stands today. South of the battlefield

ran the canyon of the Yarmouk River, while deserts occupied the north and the east of

it. The plain was mostly flat, save for a small hill called Samein .

On the 14th of August, the Roman army moved forward and started forming up to the east and north of Allan. It is debated whether the army was commanded by the Armenian general

Vahan or each of the 5 corps had a separate leader. The Byzantine army positioned itself

as follows: the light Ghassanid cavalry of Jabala was stretched across the plain as the

vanguard, with the objective of screening the army and skirmishing with the enemy. Qanateer

commanded the left flank, while Gregory was on the right flank, and 2 central corps were led by Dairjan and Vahan. The Romans had spear and sword infantry in the first rank, archers

in the second, and cavalry behind them. Although Abu Ubaidah was the overall commander

appointed by the caliph, sources claim that he allowed Khalid to be the one giving the orders. The Muslim force matched the widths of the Roman army, but as it was smaller,

its formation wasn’t as deep. Khalid moved some of his light cavalry to the vanguard

to observe the Romans. The infantry was divided into 4 corps made up of 9 units each, with

infantry in front and the archers behind them . There were 3 cavalry units behind each flank

and center, while Khalid’s mobile cavalry unit served as a reserve. The Arab commander’s

plan was to defend and tire his foe, and then counter-attack when possible. Both armies

had a southern flank secured by the river Yarmouk, while the northern flank bordering the desert offered a chance to outflank the enemy.

The battle of Yarmouk started on August 15th, 636, with the Roman light cavalry vanguard

moving behind the main army, mostly reinforcing the left flank cavalry. The Arab vanguard

did the same and joined the main cavalry units. It is unusual to see a battle fought in this

era which wasn’t started by a clash of light skirmishers, but the sources didn’t mention

this happening, instead insisting that the champions of both sides dueled for a few hours.

In any case, after the screening forces pulled back, a third of the Roman infantry advanced

across the front at midday. Soon the Roman footmen clashed with their counterparts, while the archers in the second rank skirmished, sending volleys above the heads of their infantry.

The details of this first day are scarce, but it is possible that the Byzantines decided

that a reconnaissance in force would provide benefits – their attack was slow and lacked

determination. After a few hours of fighting, they disengaged and returned to their initial

positions. The first day of battle was over and the sides returned to their respective

camps. At night a few Roman light cavalry units moved

forward, but they were caught by their Arab counterparts and forced back. These raids

were seemingly disjointed and lacked an objective, as they were not conducted by nearly enough

troops to do much damage, however, they allowed the Romans to form up in the darkness without

alerting the enemy. The plan was to attack the Muslims as early as possible, not giving

them the opportunity to get into formation. Indeed, the whole Roman army attacked before

dawn; some sources claim that they knew of the Muslim religious rites - that one of their prayers happened at this time - and decided to use it to their advantage.

Unfortunately for the attackers, the same light cavalry patrols who fought them during the night were ordered to remain in front, and as soon as the Romans came into contact

with these forward units, the Arabs retreated to their main force and informed them of the impending attack. To the surprise of the Romans, their foes managed to prepare for the attack.

However, they had their orders and so the second day of the battle began. The Roman plan was to tie up the Muslim army’s center and pressure its wings. To that end,

the attack in the middle was relatively passive. The Byzantine left attacked the Muslim right

head-on. The first two attempts to break through failed, but the Byzantines had a numerical

advantage and used it: fresh troops moved to the front, and the third attack pushed

the Arabs back. Some of them started retreating towards their camp and some joined the center-right.

This opened a way for a counterattack by the Arab right-wing cavalry. Its charge wasn’t

strong enough to force the Romans back, but tied them up for some time, allowing the infantry

to retreat. Soon the cavalry was unable to withstand the pressure and also retreated.

Later Muslim sources mention that the wives of the retreating warriors shamed them into returning to the battle. We don’t know if that is true, but the Arab right flank reformed

and started marching towards the approaching enemy. Meanwhile, the Roman right, which was probably made of the best heavy infantry in the empire,

was even more successful. Some sources mention that it was fighting in a testudo formation,

but that is probably an anachronism. In any case, the first or the second attack by this

group drove the Muslim left flank back, and they hastily retreated towards the camp. Similar

to what happened on the other side of the battlefield, the Muslim cavalry attempted to stem the enemy advance with a counterattack, but it failed, and the horsemen joined their

infantry en route to the camp. The sources once again claim that their wives urged them

to return to the battle and even threw stones at their husbands. As the Roman right was

slower due to its heavier armour, the Arabs had more time to rearrange their line and

move towards the Romans. An attentive viewer might ask, why the Byzantines

didn’t exploit these breakthroughs by pouring troops between the gaps in the Muslim formations

or by outflanking the enemy right by widening the front . In truth, we don’t have answers

to these questions, but it can be assumed that the fresh Muslim cavalry in the center

and in the reserve possibly discouraged the former, while the latter was dangerous due

to the fact that the Arabs had already used desert terrain numerous times in the past to outflank the Byzantines. It was noon, and Khalid had been just watching

the battle until that moment, but seeing the return of the wings spurred him into action, taking the command of the cavalry in the center. First, his united cavalry force charged to

the right, and moments after joining up with the right wing, attacked the enemy left. The

Romans didn’t expect an attack from the flank, and were forced to retreat to their original positions, losing men along the way. To the south, the left of the caliphate’s

army was about to engage the Byzantine right. Initially, the Arabs were having the worst

of the fight and were about to break and flee again, however, Khalid was on his way. He

sent one unit of his cavalry to exploit the gap between the enemy right and center-right,

and charged the rest into the side of the Roman right. As mentioned, this was the best

Roman infantry, so they resisted longer than their counterparts and suffered fewer casualties,

but still retreated. The cavalry unit sent to attack the Roman

center right surprised the latter, managing to break in and killing the commander of this

group . The Romans recovered from their surprise and pushed back the attackers. However, seeing

that their flanks were retreating, the center also broke off and returned to their starting

positions. Both parties probably suffered similar casualties,

with the majority of the Arab losses during the early retreat. The Roman right lost most

troops and that would prove to be important during the next day, as this detachment started

its advance alongside the whole army, but stopped well short of the enemy army with

archers on both sides entering a halfhearted skirmishing contest. Meanwhile, Roman center-right

engaged the Arabs, but this attack only served to tie-up this portion of the opposing army.

The main attack targeted the right and center right of the Muslim army and although initially the Roman onslaught was slowed, their numbers started to play role. Muslims started to retreat,

especially on the right flank, where their line was pressed all the way to the camp yet again. This allowed the Romans to increase the pressure on the rightmost units of the

Muslim center right and start turning the line. Amr’s corps finally reformed and returned

to the battle, but all their efforts only managed to stabilize the line. The Arab cavalry

in the second line attempted to outflank the Romans, but Qanateer moved his to block off

this advance. Seeing that the Roman right is passive, Khalid deduced that his left is

safe and moved the reserve cavalry to the right and charged the Roman flank. The Byzantine

commander attempted to move more troops from his second rank to widen his front, and it

worked for some time. However, the Romans now lacked the deepness and with this advantage

negated, the Arabs in the other parts of the line started to push back. Approaching dusk,

the continuation of the battle impossible and the attackers disengaged, retiring to

the initial line. It is clear that the Romans were getting frustrated, as they expected

their numbers to prevail at this point of the engagement. In the first three days, the

Romans probably lost more troops, but they still outnumbered the foe, meanwhile for Khalid,

the main worry was the losses among the Yemeni archers and on the right flank.

The Roman plan for the next day was to attack the right half of the Caliphate’s army to divide it and encircle each corps separately, and then do the same with the left half. To

that end their left attacked the Muslims and soon the right flank of Khalid’s army was

shoved back yet again, but not as far as in previous days. Made mostly of the Armenians,

Roman center left was equally successful against the Muslim center right. This time the Roman

troops were able to turn this portion of the Arab line, which opened up space between their

corpses and the Christian Arab light cavalry, which was stationed in reserve behind the

center, was commanded to charge into this gap. The Muslims were suffering heavy casualties

and it was becoming clear that Khalid needs to move to the area to stop the Romans from

winning. Before he did that though, he sent word to the left and center left, ordering

them to advance and tie up the forces in front of them.

With that the Arab commander divided his cavalry in two halves. One of them moved to the left

and attacked the Armenians from the side and rear, while Khalid himself moved against the Christian Arabs. The arrival of the reinforcements has invigorated the beleaguered Muslims and

they counterattacked. The fight here continued for a few hours, until eventually the Muslims

started gaining the upper hand. Engaged from 3 sides, the more heavily armoured and disciplined

Armenians suffered some casualties, but still were able to retreat in a relative order.

Their Christian Arab allies weren’t as able to defend themselves and lost many hundreds

before they were able to return to their initial position. Seeing that their center has fallen

back, the Roman left also disengaged. However, the left half of the Muslim army

was still in melee. Initially, the Arabs had the upper hand as their charge surprised the

Romans, but their commanders steadied the troops and soon they were pushing back. The

small number of Arab archers proved to be their undoing, as the Romans had the upper hand in the skirmishing. Apparently, the arrows did so much damage to the forces of the Caliphate,

that later Arab sources called it the “Day of Lost Eyes”. Unable to withstand the volleys,

the Arabs started to pull back. Shortly after, they were followed by the Romans. This attack

had the Muslim forces on the back foot and in full flight. All of them, except the leftmost

unit of the center, which managed to crush the enemy detachment in front of it and attacked

the right side of the Roman center. Eventually this group was overwhelmed.

The Muslim withdrawal stopped around the camps, but they were chased by the Romans. According

to the Arab sources the Muslim women joined their brethren in the fight against the attackers.

It is impossible to confirm it, but it seems that by the end of the fourth day of the battle,

the Romans were either pushed back or disengaged on their own. Both sides were extremely tired

and battered. Some sources mention that there was an attempt to negotiate from the Romans

and that the Arabs have refused. But in any case, the armies spent the 19th of August

resting. Khalid made just one change to the formation. All of his horsemen were drawn

into one large detachment behind the right-wing infantry, save for one cavalry unit which

was sent north into the desert. At the dawn of August 20 – the 6th day of

the battle both sides charged and engaged in the melee across the line. After the melee

began, Khalid sent portion of his cavalry forward with an order to attack the side of

the Roman left, but upon their approach Roman cavalry wheeled around their footmen and blocked

the advance. That was the moment the Arab commander was waiting for, as the rest of

his horsemen moved forth attacking the Roman cavalry from the side and rear. Soon the Roman

horsemen was crushed and the Arabs attacked the infantry, which broke under the attack

from three sides and started falling back into the center. The Muslim right now attacked

the Roman center left from the flank and rear. Meanwhile, the commanders of the Roman army

noticed that their left-wing cavalry was routed from the field by the consolidated Arab cavalry,

and they attempted to counter that by bringing their mounted troops together. Unfortunately

for the Romans, it was too late and before they were able to form up, Khalid smashed

into them routing them. The Roman cavalry wasn’t able to resist for long and promptly

started to leave the field of battle. Back east the Armenians were defending the

attack from 2 sides and for now were able to hold off the assailants. However, after

Khalid dealt with the Roman cavalry and made sure that they won’t return, his horsemen

charged into the rear of the Armenian formation. They collapsed under the charge and started

retreating to the southwest. The Arabs repositioned to attack the center right and right of the

Roman infantry, but before they did, the latter fled on their own, again to the southwest,

towards the only crossing over the river, all the while the Muslim cavalry blocked off their retreat from the north and footmen from the east. The remains of the Roman army were

hoping to cross Wadi-ur-Raqqad, but the 500-strong Arab mounted unit sent away into the desert,

actually was commanded to block off this crossing. Understanding that they were in a trap, the

Roman officers attempted to form up some kind of defensive line, but before they could do it, they were attacked by the cavalry from the north and infantry from the east. It was

a slaughter and many thousands were killed in this encirclement, with some units managing

to cross the rivers by swimming. Around half of the Roman army lay dead on the plain of

Yarmouk, while the Muslims lost less than fifth of their troops.

At this point in this story, we have to leave the Syrian front, as things have started heating

up in Iraq. In the aftermath of the decisive victory at the battle of the Bridge, Persian

forces made no moves to capitalize on it, either hoping that the attack was over, or

being preoccupied with other matters. This gave Caliph Umar time to come up with a response.

Lacking an immediate source of manpower, the pragmatic Rashidun caliph raised another army

from the previously untapped tribes who rebelled against the caliphate during the Ridda Wars,

including the Banu Tamim and Banu Jadila. These warriors, supplemented by additional

contingents mustered by Umar, were gathered and sent north, but problems were still present.

Quarreling between many of the tribal chiefs prompted the caliph to appoint a trusted paragon

to supreme command, who was absolutely beyond reproach. After being talked out of leading

the army himself, Umar’s commander would be Sa’d Ibn Abi Waqqas, the seventh person

to embrace Islam, and a companion of the prophet. The presence of such a respected general united

the army in spirit. Additionally, many more warriors joined themselves to Sa’d’s invasion

force as it marched north up the Medina-Hira road in May of 636. By the time it reached

the Euphrates region for a second time, the Muslim army was probably the most formidable

Persia had faced so far. Unfortunately for Sa’d, resistance to his advance was soon

in coming. The best Sassanid general, Rostam, who basically ruled the court of the 12-year-old shah Yazdegerd

III, wanted to fight smaller battles to minimize risk, but that decision was unpopular with

the nobles and commoners alike, as the battle of the bridge probably made the empire complacent.

Therefore, the general departed the Persian capital at the head of a massive imperial

force, beelining straight for the Muslims encamped near Qadissiyah.

Battle of Qadisiyyah

The two opposing armies finally caught sight of one another across the span of the al-Atiq

canal about 30 miles east of Hira. After an exhausting march in the midst of Iraq’s

blistering summer, Rostam ordered his men to take up positions and encamp across from

Sa’d’s army. Rather than immediately mounting an assault across the canal, the bulk of both

armies remained on their own side of the waterway for several months, with the peace only punctuated

by small scouting missions and raids. Rostam probably knew that the previous Islamic army

had been defeated during a botched river crossing, and was therefore content to wait and receive

Sa’d’s attack, hoping it would happen again. The Muslims, meanwhile, were fighting a two-front war, so keeping the Mesopotamian army passive,

for the time being, was prudent. In Syria, their army was engaged against the Romans

in a campaign which culminated in mid-August, at the Battle of Yarmouk. With the Christian

empire’s war machine broken, Umar was free to dispatch reinforcements to Sa’d’s force.

In the hope of keeping Rostam occupied, the Muslim leader sent repeated embassies to treat

with his Persian counterpart, demanding that the Zoroastrians submit to Islam in return

for peace. With the Sassanid commander unwilling to convert and reinforcements streaming into

their camp, the Muslims challenged their enemy to battle, arraying their forces in formation

and allowing the Sassanids to cross the canal, withdrawing a mile to the rear. With the al-Atiq

canal bridge occupied by Muslim guards, Rostam’s imperial army spent the night hours damning

the waterway with debris to enable passage. At dawn Rostam, seated on his throne, ordered

his army across and had the army advance in battle formation against the arrayed Muslim

forces. The climactic struggle for Persia was about to begin. The army under the authority of

Rostam Farrokzhad was likely made up of, at most, 60,000 Sassanid troops. Even a Sassanid

field army at the absolute apex of the empire’s power probably would not have been able to

muster such massive numbers, and it is even more unlikely that the politically divided,

militarily exhausted realm of 628 onwards could bring to bear anything more than 60,000.

Rostam’s bulwark was also a multi-ethnic army, having come together from regions all

across the vast expanse of the territory ruled by the House of Sasan, from Azerbaijan to

Khurasan. It included among its ranks Kurds, Armenians, Turks, Arabic allies and units

from many other peoples. The right and left center units of the imperial army were under the command of Jalinus and

Beerzan respectively and, in total, comprised 30,000 warriors - 20,000 melee infantry and

bowmen in the first line and 10,000 cavalry in the second. Among these troops were 10,000

professionally trained Persian Immortals, revered elite fighters who chained themselves

together as a signal to the enemy that they were prepared to die rather than retreat.

Bounded by swampland which was difficult to traverse, the Sassanid left and right wings

were led by Mihran and Hormuzan, both illustrious generals drawn from highborn Persian clans.

Each led 10,000 infantry in their front rank, backed by 5,000 cavalry behind. In front of

Rostam’s line was a screen of 33 mail-clad elephants. 18 of them were deployed in the

center while the remainder were split equally on either wing. Rostam himself, donning ornate

armour, mounted raised his throne just behind the center, accompanied by a small strategic

reserve. About a mile to the west, Sa’d’s 30,000 warriors drew up in a manner that mirrored

their adversaries - four tribally organised divisions with infantry in the first line

and cavalry in the second. In addition to the Muslim forces from Arabia proper, Christian

Arabs from the border of Sassanid territory and even some captured Persian officers had

joined the army after converting to Islam. Although Sa’d Ibn Abi Waqqas was capable of deploying his army properly, ailments and

injury prevented him from mounting a horse and exercising effective tactical control.

Instead, the companion-general appointed a trusted deputy Khalid ibn Urfuta to carry

out his immediate orders, and took up a strategic position atop the fortress of nearby Uzeib.

The various units were commanded by their tribal chieftains, and included men such as

Shurabil Ibn Simt - a veteran of the Ridda Wars and Syrian campaign - who led the Muslim

left wing. As Rostam’s large army continued to form up, Muslim soldiers took part in their

usual noon prayer, donned their armour and waited. By the early afternoon hours, the

massive Persian army was finally ready to fight. Rostam’s plan was simple and to the

point - smash both flanks of the enemy army and then smash into their exposed center.

The Battle of al-Qadissiyah began with a heavy barrage of arrows loosed by the Sassanid archers,

whose superior bows and higher quality arrows inflicted massive casualties on their lightly-armoured

counterparts. The Muslims attempted to return the favour, but their low powered bows and

inferior arrows resulted in the missiles bouncing harmlessly off the Persian heavy armour. The

amused Sassanid troops mocked the Muslim archers by repeating the word “Spindles, spindles!”

as the impotent arrows fell harmlessly.

With most of the Islamic front line pinned in place by Rostam’s lethal storm of arrows,

the general ordered the 7-strong elephant corps on his left to lead a charge directly

at the Muslims opposing him, followed by the rest of the troops. Frightened by the oncoming

titans, the Rashidun mounts forced their riders to scatter from their position, leaving the

infantry exposed. Beset by Mihran’s flank and lacking cavalry support, the Muslim warriors

fell back slowly, suffering casualties but not breaking under the assault. Sa’d, witnessing

the danger his right flank was in from Uzeib, had two units of cavalry from the unengaged

centre dispatched to reinforce and shore up the line. One of these contingents struck

Mihran’s troops in the front while the other hit them in the flank, pushing the Persians back to their starting position after a fierce fight.

Observing that his attack on the Muslim right was stalling, Rostam completely changed tack.

He dispatched part of his immediate reserve under Bahman to keep that part of the Muslim

army locked in place, then ordered the Sassanid right and right-centre to advance, fronted

by elephants and covered by another deadly volley of arrows. Again, the vanguard of elephants

panicked Rashidun mounts and forced the horsemen to flee for infantry cover.

This state of affairs could not continue if victory for Islam was to be attained. Sa’d,

realising he had to do something about the Sassanids’ assault beasts, had orders conveyed that light troops from the Arabian Bani Tamim tribe deal with them. Darting in and amongst

the massive elephants with considerable skill and daring, the agile warriors cut the cables

which kept the elephants’ mounting platforms atop the animals, and showered the occupants with missile fire. A vast number of the isolated elephant-riders were killed where they stood,

while the rest led their exhausted war mounts back behind the main Persian line. The general

Sassanid attack on this side of the field was also wrestled back.

In an attempt to take advantage of his enemy’s lack of elephants, Sa’d ordered a general

attack all across the front. It is said that while the Sassanids were equipped better than

their foe, the Muslims were superior fighters. This level of skill allowed a unit in Sa’d’s centre to punch through the Persian line and get close to the enthroned Rostam. Descending

from his position, the general drew his sword and entered the fray personally along with

some retainers. With the army’s morale bolstered by the presence of their leader, the Muslim

counterattack was repelled and the front re-established. By nightfall, the last of the days’ fighting

had come to an end. This first dreadful day, also known as the ‘Day of Disorder’ by

the battered Rashidun warriors, was over.

The wounded were gathered and cared for by women in the Muslim camp and trained surgeons

of the Sassanid army while the remainder rested. When dawn came, both armies once again lined

up for battle, facing off until midmorning. At around noon, a thousand reinforcements

from Syria under Qaqa bin Amr began streaming onto the field to reinforce the Muslim army,

coming ten at a time as to give the illusion of vast numbers. This increased the morale

of the Muslim army tenfold and Sa’d immediately ordered another charge all across the line.

Despite the heavy casualties that his troops inflicted on the Sassanids, the enemy ranks

remained coherent and unbroken, mainly due to the force of their heavily armoured cavalry.

Casualties increased as the fighting grew more and more brutal, but after two hours

of fruitless fighting, both sides pulled back. The Muslims were trading well - four dead Persians for each of their own - but Rostam, trusting in his superior numbers, was content

to grind Sa’d’s force into the dust.

On the Muslim side, Qaqa, displaying his energetic and restless nature, used the break in fighting

to cover the camels that the Rashidun army brought with wooden structures, making them

look to the untrained eye of a horse like unfamiliar, terrifying beasts. When fighting

resumed not long after, the disguised camels were paraded in front of the charging Persian

cavalry, spooking the horses into breaking ranks. Sensing an advantage, Sa’d had the

army attack along the entire front again. This time, without elephants or cavalry to

bolster their ranks, zealous Muslim warriors scythed into the Persians units, viciously

routing many of them towards the waterway behind and almost causing the entire Sassanid

army to buckle with the shock. However, Rostam’s personal intervention and unmoving confidence

allowed his shattered contingents to get back into the fight.

Throughout the evening hours, Persian and Rashidun troops engaged in a slogging match which, as the sun dipped beneath the horizon, managed to painstakingly throw the Muslims

into retreat. With that, both exhausted armies retired for the night. When daylight came

on the third day and the armies were arraying for battle, Sa’d’s troops were met with

an unwelcome surprise. The enemy ranks parted briefly and through them marched the mighty

elephants, recovered and rearmed, now each surrounded by a protective ring of infantry

and cavalry. When midmorning came, Rostam had his archers unleash another extended arrow volley which

locked the Muslims in place. As this barrage concluded, the entire Sassanid army, fronted

by the terrifying elephants, began inexorably trudging onward. Suddenly, as they approached

Sa’d’s line, the infantry shielding each elephants’ front shifted aside according to plan, enabling the giant war beasts to crash into the Muslim line at close range.

The riders were able to escape and fled without delay, but the infantry wasn’t so lucky.

Sa’d’s entire army was brutally shoved back, losing hundreds of men who were gored

by tusks, crushed by the elephants’ feet, or put to the sword by Persian arms. Rostam

caught the smell of blood in the water. In order to end the battle, he sent a cavalry

division on a deep flanking attack against the Uzeib Castle itself, but this was rapidly

countered by a unit of Muslim riders. Although that attempt failed, the army of Islam was

visibly about to disintegrate, despite the coming of even more reinforcements from the

west. Taking advice from a defected Persian soldier at the last possible moment, Rashidun light

infantry slid through the ranks, surrounded the two lead elephants and blinded them, before

swarming the creatures and their onboard missile troops. With the elephant alphas killed, other

beasts along the line were overwhelmed and killed in the same manner. Many others, driven

into a rage by pain and unable to see through mutilated eyes, turned 180 degrees and stampeded

towards the canal, crashing through the Persian ranks and disordering Rostam’s army. Sa’d

ordered yet another a full-scale assault, impacting on the Sassanids with devastating force. al-Qadissyiah was devolving into a war of attrition. Not even darkness on the

‘Day of Hardship’ brought the fighting to an end, but the soldiers’ sheer exhaustion

gradually led the troops to disengage at sunrise the next day.

Both armies seemed to be at breaking point, but it still wasn’t clear who the victor would be. As both armies rested, Qaqa decided to make a decisive move. Under the cover of

a brief sandstorm, he and 700 troops launched an attack on the blinded Persian center, breaking

through the line and approaching Rostam. Isolated and disoriented, the Sassanid general was

found by a Rashidun soldier and slain. Fighti

ng continued until rumours of their commanders

fate spread around the Persian army. At that point, the center finally cracked and routed

towards the river, followed shortly after by both flanks. The imperial army of the Sassanid

Empire had been defeated. The Sassanids lost more than 20 thousand. While the Muslim losses

were less than 10 thousand. Although the Muslims seemingly scored decisive victories against two of the strongest empires

of the period, the war in the region was hardly over.