Within a century or two of Muhammad's death in 632, only a few Christian sects remained in Arabia, Islam's origin.
In Syria and Persia, where Christian populations were more concentrated, accommodating practices prevailed. Certainly, Arab conquest of these nearby areas involved violence, primarily against existing Byzantine and Persian armed forces, but not to force conversion.
Thus, the Nestorian Christian communities of Syria, Iraq, and Persia, sometimes referred to as the Church of the East, resisted Islam's assault, but only as diminishing communities of second-class subjects, with minorities barred from spreading their message to Muslims.
Later, in the thirteenth century, the Mongol conquest of China provided a small window of opportunity for Christian revival, as the religiously liberal Mongols accepted Nestorian Christians as well as members of other faiths. Several prominent Mongols, including one of Chinggis Khan's wives, converted to Christianity.
A new administrative system granted nominated generals civil control over the empire's provinces and permitted them to recruit troops from the region's landowners. The empire's naval and mercantile vessels operated in both the Mediterranean and Black seas from that territorial base.
The Byzantine state was a magnificent creation in its height. In Constantinople, political power remained tightly centralized, with the emperor claiming to rule over all of creation as God's worldly representative, referring to himself as the "peer of the Apostles" and the "single ruler of the universe."
Due to attacks by aggressive Western European nations, Catholic Crusaders, and Turkic Muslim invaders after 1085, Byzantine territory shrunk. The Turkic Ottoman Empire dubbed the "sword of Islam" at the time, finally seized Constantinople in 1453.
The imperial court attempted to replicate the majesty of what is believed to be God's heavenly court, although it was more akin to ancient Persian imperial magnificence.
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