Comprehensive Study Notes on World History: Medieval Europe, West Africa, and the Islamic Golden Age

In West Africa, land was not owned privately, making labor the primary source and measure of wealth.
Slaves served as domestic household workers, were inherited by biological children, and were traded in a large indigenous market, with an estimated $750$ to $1,500$ individuals enslaved annually through warfare.
By the 15th century, Sub-Saharan Africa had a population of approximately $40,000,000$ —slightly less than Europe—spread across a vast landmass with low population density.

In $1400$ , China possessed a population of $85$ to $100,000,000$ under a unified empire, whereas Europe was divided into hundreds of distinct political units.
Following the collapse of the Roman Empire—which ruled Britannia for $400$ years, France, and parts of Germania along the Rhine River like Trier—European sovereignty fragmented into localized feudalism led by regional strongmen and knights.
Serfs worked three to four days per week on the lord's manor and three days on their own land, remaining bound to the estate in an illiterate society where literacy was mostly confined to Roman Catholic monks writing in Latin (e.g., King Charlemagne around $800$ was illiterate).
Between $1000$ and $1500$ , European warfare intensified; the introduction of cannons (developed in China and refined through bronze church bell casting) destroyed traditional stone castles and drove the formation of centralized territorial states funded by urban wealth (such as Paris).
In $1453$ , the Ottoman Turks captured Constantinople, and the King of France utilized cannons to expel the English, bringing the Hundred Years' War to an end.

In $1453$ , Catholic monarchs Ferdinand and Isabella deployed a siege train of $180$ cannons to drive Muslim rule from Granada (Andalusina).
Ferdinand and Isabella instituted the Spanish Inquisition, executed thousands, and ordered the expulsion of all Muslims and Jews who refused conversion to Christianity.
Bertolomeo de las Casas documented Spanish conquistadores executing Los Tainos by burning and hanging in Puerto Rico.
Prior to the reconquest, Muslim rule ( $700\text{s}$ to $1400\text{s}$ over $90\%$ of Spain) permitted Christians and Jews to practice their faiths upon paying a head tax, influencing the Spanish language such that $1$ out of $4$ words derives from Arabic.
Early American founders established the First Amendment (freedom of religion) to explicitly reject European patterns of religious persecution and fragmentation.

The harsh terrain of the Arabian desert shaped culture around strong group solidarity, camel trading, raiding, and survival skills necessitated by scarce water and resources.
Prophet Muhammad, originating from the Quraysh tribe in Mecca, received revelations starting in $610\,\text{AD}$ , migrated to Medina in $622\,\text{AD}$ , and consolidated Arab tribes prior to his death in $632\,\text{AD}$ .
Early Islamic expansion relied on strategic agreements, military flexibility, and religious tolerance—such as sharing worship facilities in Damascus with Christians—rather than forced conversion.

The Islamic Golden Age integrated knowledge across cultures, adopting the Indian numerical system (including zero, $0$ ), inventing algebra, naming stars, and advancing ophthalmology and medicine.
The Abbasid Caliphate established its capital at Baghdad, constructed as a circular city along the Tigris River reflecting a $360$ -degree mathematical focus.
The Arabic translation movement translated Greek, Roman, Persian, Indian, and Chinese texts into Arabic, treating ancient manuscripts as high-value wartime plunder.
Educational institutions known as madrasas proliferated across cities, establishing academic status and reliable livelihoods for scholars.

Between $800$ and $1000$ , Scandinavian Vikings launched raids across England, Scotland, and continental Europe along river routes like the Seine, Volga, and Dnieper.
Viking longships featured sleek engineering and shallow drafts, allowing $40$ to $50$ rowers to navigate shallow inland waterways and raid deep into territories.
Viking raids forced local populations to seek defense in fortified structures and secluded islands like Mont-Saint-Michel.
By $1200$ , major Gothic architectural masterpieces emerged across Europe, including Cologne Cathedral in Germany and Chartres Cathedral and Notre Dame in France.

Question: How does the desert environment enforce group dependency compared to regions like East Tennessee?
- Response: East Tennessee provided abundant water and wild game (turkeys, bear, deer), allowing individual self-sufficiency (such as Davy Crockett and Rebecca), whereas the desert lacked water and wildlife, forcing individuals to rely strictly on tribal solidarity, trading, and raiding for survival.
Question: What is the significance of solitude across major spiritual and historical movements?
- Response: Solitude serves as a creative restriction and parameter that fosters inspiration and transformation, as seen with Muhammad in the cave, Jesus Christ during $40$ days in the wilderness, Buddha under the banyan tree, Saint Francis on the mountain, and Henry David Thoreau at Walden Pond.
Question: Why were fortified structures constructed on secluded islands during the Middle Ages?
- Response: Island locations provided natural defense and isolation against Viking naval incursions during the $800\text{s}$ and $900\text{s}$ .
Question: What engineering feature allowed Viking ships to navigate shallow European rivers?
- Response: Viking longships sat high on the water with a shallow draft, enabling them to navigate shallow rivers without sinking deep into the water.