In Islam, the title of a coming messiah who will establish a reign of justice on Earth. The title has been assumed by many Muslim leaders, notably the Sudanese sheik Mohammed Ahmed (1848–1885), who headed a revolt 1881 against Egypt and 1885 captured Khartoum.
His great-grandson Sadiq el Mahdi (1936– ), leader of the Umma party in Sudan, was prime minister 1966–67. He was imprisoned 1969–74 for attempting to overthrow the military regime.
Among Mohammedans, the last imam or leader of the faithful. The Sunni, the largest sect of the Mohammedans, believe that he is yet to appear.