During the Ottoman period the Emirate was not hereditary, and owed its succession to direct nomination by the Ottoman Porte.[3] A dual system of government existed over the Hejaz for much of this period.[12] Ruling authority was shared between the Emir, a member of the ashraf or descendants of Muhammad, and the Ottoman wāli or governor.[12] This system continued until the Arab Revolt of 1916.[12] Apart from the Emirs of Mecca, Ottoman administration in the Hejaz was first at the hands of the Governor of Egypt and then the Governors of Jeddah. The Eyalet of Jeddah was later transformed into the Hejaz Vilayet, with a governor in Mecca.[13]