During the five centuries that followed Muhammad’s death, his teachings came to be revered in large parts of the world, from Spain to Afghanistan. Although in some ways similar to the earlier spread of Buddhism out of India and Christianity out of Palestine, the spread of Islam occurred largely through military conquests that extended Muslim lands. Still, conversion was never complete; both Christians and Jews maintained substantial communities within Muslim lands. Moreover, cultural contact among Christians, Jews, and Muslims was an important element in the development of each culture.

Muslim civilization in these centuries drew from many sources, including Persia and Byzantium, and in turn had broad impact beyond its borders. Muslim scholars preserved much of early Greek philosophy and science through translation into Arabic. Trade connected the Muslim lands both to Europe and to India and China.

During the first and second centuries after Muhammad, Islam spread along the Mediterranean coast of North Africa, which had been part of the Roman world. The next chapter explores other developments in the enormous and diverse continent of Africa during this time. Many of the written sources that tell us about the African societies of these centuries were written in Arabic by visitors from elsewhere in the Muslim world. Muslim traders traveled through many of the societies in Africa north of the Congo, aiding the spread of Islam to the elites of many of these societies. Ethiopia was an exception, as Christianity spread there from Egypt before the time of Muhammad and retained its hold in subsequent centuries. Africa’s history is introduced in the next chapter.