In 1435 the people rose against the tyranny of the Bani Nebhan and restored the imamate of the tribe al-Azd.
According to the Shiite Moslems, who call the office the "imamate" or leadership, no caliph is legitimate unless he is a lineal descendant of the Prophet.
The theologians tried to uphold the orthodox theory by declaring the sultanate to be subordinate to the imamate or sovereignty of the caliphs, and dependent on the latter especially in all religious matters; but their artificial theories have never modified facts.
He nominates the Sheikh ul-Islam or mufti (q.v.) of Constantinople (grand mufti), who is his representative in the imamate and issues judgments in points of faith and law from which there is no appeal; but the nomination must fall on one of the mollahs, 2 who form the upper stratum of the hierarchy of ulema.