It is apparent that the two earlier monotheisms, Judaism and Christianity, constituted an influential presence in the Hijaz, the region comprising Mecca and Medina. Indeed, Jewish communities were salient here, especially in Medina and other not-too-distant oases. Moreover, in addition to the presence of Jews and Christians, there existed a third category of individuals, the Hanifs, who, dissatisfied with their polytheistic beliefs, had developed monotheistic ideas.
Zeitlin assesses the extent to which these various influences shaped the emergence of Islam and the development of the Prophets beliefs. He also seeks to understand how the process set in motion by Muhammad led, not long after his death, to the establishment of a world empire.