Fromherz, drawing on medieval Arabic and Berber sources, analyses the myths and history surrounding the origins and rise of the Almohad Empire. He shows how Muhammad Ibn Tumart, the son of a minor Berber tribal chief, set off on his mission to reform Islam, then at a low point in its history, battered by the crusades, having lost Jerusalem and been undermined by weak spiritual and political leadership. Muhammad Ibn Tumart was proclaimed Mahdi - one who would herald the golden age of Islam - provided charismatic leadership, unwavering adherence to a fundamentalist monotheistic Islam enforced by holy war, established tribal unity, effective administration and a formidable military force. Ibn Tumart and his legacy were to prove the launch pad for empire, leading to Almohad domination of the western Mediterranean from Tunisia to Morocco and Andalusia.