The inhabitants of seventh-century Arabia mobilized for warfare in a manner new to that region of the Near East: the effort fell, albeit gradually, under central authority.1 Arabia had long been a highly variegated cultural zone, encompassing the Syrian Desert, southern Mesopotamia, and the Arabian Peninsula. Acting in tandem, largely nomadic tribal forces accepted the leadership of sedentary townsmen, the great number of whom belonged to the Quraysh, an influential tribe of two towns of the Hejaz region, Mecca and Medina. If Yemen and south Arabia had long known the rule of kings, and, hence, more formal military organization, only now did the central and northern stretches of the Peninsula and southern Syria experience what can thereby be considered as early state formation. The effort was driven by an equally untested set of ethical and spiritual teachings. A charismatic figure, Muḥammad ibn ʿAbdallāh (570–632), preached a strict monotheism; these teachings served as the seedbed of what would soon be known as Islam.