Muhammad Ahmad ibn ʿAbdallah

Muḥammad Aḥmad ibn ʿAbd Allāh ibn Faḥal (Arabic: محمد أحمد بن عبد الله بن فحل; 12 August 1843 – 21 June 1885) was a Sudanese religious and political leader. In 1881, he claimed to be the Mahdi and led a war against Egyptian rule in Sudan, which culminated in a remarkable victory over them in the Siege of Khartoum. He created a vast Islamic state extending from the Red Sea to Central Africa and founded a movement that remained influential in Sudan a century later.

From his announcement of the Mahdist State in June 1881 until its end in 1899, the Mahdi's supporters, the Ansar, established many of its theological and political doctrines. After Muhammad Ahmad's unexpected death from typhus on 22 June 1885, his chief deputy, Abdallahi ibn Muhammad took over the administration of the nascent Mahdist State.

The Mahdist State, weakened by his successor's autocratic rule and inability to unify the populace to resist the British blockade and subsequent war, was dissolved following the Anglo-Egyptian conquest of Sudan, in 1899. Despite that, the Mahdi remains a respected figure in the history of Sudan. In the late 20th century, one of his direct descendants, Sadiq al-Mahdi, twice served as prime minister of Sudan (1966–1967 and 1986–1989) and pursued pro-democracy policies.