Nizar
Abū Manṣūr Nizār ibn al-Mustanṣir was a Fatimid prince, and the oldest son of the eighth Fatimid caliph and Isma'ili imam, al-Mustansir. When his father died in December 1094, the military strongman, al-Afdal Shahanshah, raised Nizar's younger brother al-Musta'li to the throne in Cairo, bypassing the claims of Nizar and other older sons of al-Mustansir. Nizar escaped Cairo, rebelled and seized Alexandria, where he reigned as caliph with the regnal name al-Muṣṭafā li-Dīn Allāh. In late 1095 he was defeated and taken prisoner to Cairo, where he was killed by immurement. Many Isma'ilis, especially in Persia, who rejected al-Musta'li's imamate and considered Nizar as the rightful imam, split off from the Fatimid regime and founded the Nizari branch of Isma'ilism, with their own line of imams who claimed descent from Nizar that continues to this day. Later during the 12th century some of Nizar's actual or claimed descendants tried, without success, to seize the throne from the Fatimid caliphs.