What made possible the spread of Islam, and what forms of government were established to rule Muslim lands?

According to Muslim tradition, Muhammad’s preaching at first did not appeal to many people — for the first three years he attracted only fourteen believers. In preaching a transformation of the social order and calling for the destruction of the idols in the Ka’ba, Muhammad challenged the power of the local elite and the pilgrimage-based economy. As a result, the townspeople of Mecca turned against him, and he and his followers were forced to flee to Medina. This hijra (hih-JIGH-ruh), or emigration, occurred in 622, and Muslims later dated the beginning of their era from it.

At Medina, Muhammad attracted increasing numbers of believers, many of whom were Bedouins who supported themselves by raiding caravans en route to Mecca, setting off a violent conflict between Mecca and Medina. After eight years of strife, Mecca capitulated. In this way, by the time Muhammad died in 632, he had welded together all the Bedouin tribes.

Muhammad displayed genius as both political strategist and religious teacher. He gave Arabs the idea of a unique and unified umma (UH-muh), or community, made up of all those whose primary identity and bond was a common religious faith, not a tribal tie. The umma was to be a religious and political community led by Muhammad for the achievement of God’s will on earth. In the early seventh century the southern Arab tribal confederations lacked cohesiveness and were constantly warring. The Islamic notion of an absolute higher authority transcended the boundaries of individual tribal units and fostered political consolidation. All authority came from God through Muhammad.