Muhammad ibn Tumart was the Masmuda religious reformer and founder of the Almohad movement that displaced the Almoravid empire and unified the medieval Maghreb under a single Berber caliphal dynasty. He was born around 1080 in Igiliz, a village of the Hargha tribe of the Anti-Atlas in the Souss region of southern Morocco.
Ibn Tumart studied for more than a decade in the Islamic east — Córdoba, Alexandria, Mecca, Baghdad, and Damascus — where he absorbed the Ash'ari theological tradition, the philosophical synthesis associated with al-Ghazali, and a strict moral programme directed against what he characterised as the corruption of his age. Returning to the Maghreb in the second decade of the twelfth century, he preached publicly in Tunis, Bejaia, Tlemcen, Marrakesh, and Aghmat, repeatedly clashing with Almoravid authorities.
Around 1121 he declared himself the awaited Mahdi at Igiliz and three years later relocated his community to the more defensible mountain refuge of Tinmel in the western High Atlas. The Almohad organisation he established translated Masmuda tribal segmentation into a permanent military hierarchy under a council of ten and a council of fifty; Tinmel became both a fortified base and a centre of religious instruction.
Ibn Tumart died at Tinmel in 1130, leaving the political and military leadership to his caliph and successor Abd al-Mu'min, who took Marrakesh in 1147 and unified the Maghreb from the Atlantic to Tripolitania within fifteen years. The Tinmel mosque, built on the site of Ibn Tumart's tomb, survives in ruined but recognisable form in the High Atlas; it was substantially damaged in the September 2023 al-Haouz earthquake.