<P> Around AD 500, Clovis I, the King of the Franks, became a Christian and united Gaul under his rule . Later in the 6th century, the Byzantine Empire restored its rule in much of Italy and Spain . Missionaries sent from Ireland by the Pope helped to convert England to Christianity in the 6th century as well, restoring that faith as the dominant in Western Europe . </P> <P> Muhammed, the founder and Prophet of Islam was born in Mecca in AD 570 . Working as a trader he encountered the ideas of Christianity and Judaism on the fringes of the Byzantine Empire, and around 610 began preaching of a new monotheistic religion, Islam, and in 622 became the civil and spiritual leader of Medina, soon after conquering Mecca in 630 . Dying in 632, Muhammed's new creed conquered first the Arabian tribes, then the great Byzantine cities of Damascus in 635 and Jerusalem in 636 . A multiethnic Islamic empire was established across the formerly Roman Middle East and North Africa . By the early 8th century, Iberia and Sicily had fallen to the Muslims . By the 9th century, Sardinia, Malta, Cyprus and Crete had fallen--and for a time the South of France and Italy . </P> <P> Only in 732 was the Muslim advance into Europe stopped by the Frankish leader Charles Martel, saving Gaul and the rest of the West from conquest by Islam . From this time, the "West" became synonymous with Christendom, the territory ruled by Christian powers, as Oriental Christianity fell to dhimmi status under the Muslim Caliphates . The cause to liberate the "Holy Land" remained a major focus throughout medieval history, fueling many consecutive crusades, only the first of which was successful (although it resulted in many atrocities, in Europe as well as elsewhere). </P> <P> Charlemagne ("Charles the Great" in English) became king of the Franks . He conquered Gaul (modern day France), northern Spain, Saxony, and northern and central Italy . In 800, Pope Leo III crowned Charlemagne Holy Roman Emperor . Under his rule, his subjects in non-Christian lands like Germany converted to Christianity . </P>

Why is greece considered the foundation of western civilization