MUḤAMMAD AḤMAD (AH 1260–1302/1844–1885 CE), Sudanese preacher and mystic who claimed to be the Mahdi of Islam. Muḥammad Aḥmad ibn ʿAbd Allāh was born at Labab Island on the Nile in Dongola province of a Nubian family claiming descent from the Prophet and was brought up at Karari, just north of Omdurman. He received a traditional Islamic education and at age seventeen became apprenticed to Muḥammad Sharīf Nūr al-Dāʾim, a shaykh of the Sammānīyah Ṣūfī order. He spent seven years serving and imbibing mystical wisdom from his master who then authorized him to teach the doctrines of the order and to initiate others.

In 1870 he took up residence on Aba Island on the White Nile just north of Kosti, along with his three brothers...