Description:This study examines the marital data preserved within the Arabic genealogical works of the early ninth century CE in order to better understand the tribal relationships of the pre-Islamic Quraysh (the Arabic tribe to which Muhammad belonged). The research establishes the accuracy of the Nasab Quraysh (Genealogy of the Quraysh) and informs a more nuanced analysis of the politics of the Central Hijaz into which Islam was born.