The basic social unit of the Bedouins and other Arabs was the tribe. Consisting of people connected through kinship, tribes provided protection and support and in turn expected members’ total loyalty. Like the Germanic peoples in the age of their migrations (see “How did the barbarians shape social, economic, and political structures in Europe and western Asia?” in Chapter 8), Arab tribes were not static entities but rather continually evolving groups. A particular tribe might include both nomadic and sedentary members.

In northern and central Arabia in the early seventh century, tribal confederations led by their warrior elite were dominant. In the southern parts of the peninsula, however, priestly aristocracies tended to hold political power.

The power of the northern warrior class rested on its fighting skills. The southern religious aristocracy, by contrast, depended on its religious and economic power. The political genius of Muhammad was to bind together these different tribal groups into a strong, unified state.