Initially, Mahadism was a religious order created in Sudan in 1881, fighting in a violent and fanatic way every form of exterior influence (in particular every Egyptian presence). Later, it became an ordinary sect with a growing influence and political role in the country.

In 1881, when Sudan was under Egyptian aegis, Mohammed Ahmed ibn Abdullah pretended to be the Mahdi (the Muslim liberator, the Chosen) and the Imam (Leader of the Muslim community). He and his successors established a religious order, the Mahadiyya, including activists, the Al-Ansar (the Assistants). The Mahdi called for a Holy war against the unfaithful, including the Muslims who did not recognize his mission. His followers, fanatics, – often wrongly called Dervishes by the European, managed to beat the Egyptian troops that pursued them, and to conquer the provinces of Kordofan, Darfour and Bahr-al-Gazzal. In 1885, they even managed to take Khartoum, killed the governor-general of Sudan, General Gordon. The Mahdi extended its power to the major part of the country.

After his death in 1885, the order lost most of its force under its successor and was not able to establish an organized state. Between 1896 and 1898, an Anglo-Egyptian force, commanded by General Kitchener, took over Sudan and the order leader was killed in the battle. Resistance forces were repressed at the beginning of the century.

Nevertheless, the order survived and became an “ordinary” sect, gaining more and more political importance as one goes along. As the sect was in favor of the independence of Sudan and opposed to a union with Egypt, it even helped the Brits to fight the Ottoman influence during World War I.

From the 1950s on, the sect became the rallying point of the opposition to the military and revolutionary regime controlling Sudan, through -among others- its political branch, the Umma party. In July 1966, al-Sadek al-Mahdi, Umma leader and great grandson of the Mahdi, even became Prime Minister, but was overthrown by Noumeiri. In 1970, the sect came to organize a rebellion against the regime. Thirteen years later, al-Sadek, who did not have a predominant position in the religious structure of the sect, opposed himself against the implementation of the Sharia in Sudan. The Mahadiyya also played a prominent role in the overthrow of Noumeiri in April 1985, then at the government established by al-Sadeq one year later. The latter was overthrown in April 1989 by General Béchir, who has since then prohibited the existence of political parties.