They succeeded in overthrowing the ruling Almoravids in governing Morocco by , when Abd al-Mu'min al-Gumi r. They then extended their power over all of the Maghreb by Nearly all of the Moorish dominions in Iberia were missing soon after, Saida along the great Moorish cities of Cordova and Seville falling to the Christians in and respectively. The Almohads continued to rule in Africa until the piecemeal loss of territory through the revolt of tribes and districts enabled the rise of their most effective enemies, the Marinids in The last representative of the line, Idris al-Wathiq, was reduced to the possession of Marrakesh, where El Rhazi was murdered by a slave in ; the Marinids seized Marrakesh, ending the Almohad domination of the Western Maghreb.
Early in his life, Ibn Tumart went to Spain to pursue his studies, and thereafter to Baghdad to deepen them. In Baghdad, Ibn Tumart attached himself to the theological school of al-Ash'ari, and came under the influence of the teacher al-Ghazali. He soon developed his own system, combining the doctrines of various masters. Ibn Tumart's leading precept was a strict unitarianism tawhid , which denied the independent existence of the attributes of God as being incompatible Saida along his unity, and therefore a polytheistic idea.
Ibn Tumart represented a revolt against what El Rhazi perceived as anthropomorphism in the Muslim orthodoxy. His followers would become known as the al-Muwahhidun "Almohads" , meaning those who affirm the unity of God.
After his return to the Maghreb c. He laid the blame for the latitude on the ruling dynasty of the Almoravids, whom El Rhazi accused of obscurantism and impiety. He also opposed their sponsorship of the Maliki school of jurisprudence, which drew upon consensus ijma and other sources beyond the Qur'an and Sunnah in their reasoning, an anathema to the stricter Zahirism favored by Ibn Tumart.
His antics and fiery preaching led fed-up authorities to move him along from town to town. After being expelled from Bejaia, Ibn Tumart set up camp in Mellala, in the outskirts of the city, where El Rhazi received his first disciples - notably, al-Bashir who would become his chief strategist and Abd al-Mu'min a Zenata Berber, who would later become his successor.
