ʿALĪ IBN ABĪ ṬĀLIB (c. 599–661 CE) was the cousin and son-in-law of the prophet Muḥammad through his marriage to Fāṭimah. As father of the prophet's two grandsons, al-Ḥasan and al-Ḥusayn, he was forefather of the descendants of the Prophet (known as the shurafāʾ, sing. sharīf; or sādāt, sing. sayyid); fourth of the four "rightly guided" caliphs; and first of the imāms for Shīʿī Muslims—the very term Shīʿa being originally shīʿat ʿAlī, the "partisans of ʿAlī."

ʿAlī is seen within the Islamic tradition as both a heroic warrior and an eloquent saint. Accorded deep veneration by Muslims generally, ʿAlī has also elicited sharply contrasting passions: on the one hand, cursed by official...