illustration of angus mcbride showing the Emir of the Almohad dynasty Yaqub al-Mansur with his bodyguard, Yakub al-Mansur reigned from 1184 to 1199 with distinction. During his tenure, trade, architecture, philosophy and the sciences flourished. on July 18, 1195, he defeated the Castilian King Alfonso VIII. After victory, he took the title al-Mansur Billah ("Made Victorious by God").