Icon of Muslim conquests

Animated by the spirit of militant and expansive Islam, Muslim armies conquered Arabia, Syria, Egypt, the Persian Empire, the coast of North Africa, and Spain in the seventh and eighth centuries. The advance into Europe was not checked until Muslim armies were defeated by Charles Martel at the battle of Tours in 732. This placed many of the ancient centers of Christianity under Muslim rule and reduced the Byzantine Empire to the territory of modern Turkey and a comparatively small portion of Europe. This had two further important effects on western Christianity. It brought western Christian thinkers into contact with Islamic intellectual life, a meeting which resulted in among other things a renewed study of Aristotle as interpreted by the Islamic philosopher Averroes. It also caused western Christianity to understand itself as distributed along an axis running from north to south rather than east to west. This axis eventually would run from Scandinavia in the north to Italy in the south and would include the British Isles and the Frankish kingdom. With the West increasingly separated from the East by political and cultural events, the eastern and western churches would increasingly drift apart.