Occupied by Arab forces in 19/640, Egypt emerged as a preeminent province in the Islamic empire, ruled by the Umayyad and ʿAbbāsid dynasties. Attaining autonomy under the Turkish governor Aḥmad b. Ṭūlūn in 254/868, Egypt became an independent power in the Middle East and North Africa over the next century. Subsequent establishment of a Shīʿī caliphate under the Fāṭimids and a Sunnī sultanate by the Ayyūbids, restructured by the Mamlūks, consistently emphasised agrarian exploitation of the Nile Valley, control over Syria, and domination of Red Sea trade routes,