In traditional societies, ancestry is an important organising principle, often determining the lives of individuals or groups from the moment that they are born. In the Arab world, nasab (pl. ansÄb) or lineage was and to some extent still is, a major factor in the distribution of wordly and religious power, while administrative positions, trades, crafts and certain offices in the world of scholarship, too, often devolved along hereditary lines. Among the Shīʿa, where blood ties with the family of the Prophet through Ê¿AlÄ« and his descendants are highly regarded and a source of authority and social standing, we find a number of ansÄb works that focus exclusively on the genealogy of the twelve imams. Born into a Shīʿite family of ansÄb scholars in 11th/17th-century Medina, the author of the present work travelled extensively in the Shīʿa world in his search for information. The result is a voluminous work, rich in material, genealogical and historic. 3 vols. & supplement al-RawḠal-miÊ¿á¹Är fÄ« tashjÄ«r Tuḥfat al-azhÄr; volume 1.