Eighth Fatimid Ismaili imam/caliph in Egypt (r. 1036–94); had a paradoxical career. Was considered the pinnacle of a religio-political hierarchy, with access to the inner truths of the Quran, but he was less powerful than his viziers, especially Badr al-Jamali. Unsuccessful in ousting Turkish invaders from Palestine, he tried to enlist the support of the Crusaders, later the Fatimids' enemies. He reputedly designated his elder son, al-Nizar, as spiritual and political heir; enthronement of his younger son split the Ismailis. Nizari devotees, whose imam was now “hidden,” became the Assassins and ancestors of the largest modern Ismaili community.