In 1916, the Arab Revolt against Ottoman rule had broken out in the Hejaz, led by Hussein bin Ali, Sharif of Mecca. Although the Ottomans defended Medina, at the end of the Hejaz Railway against them, part of the Sherifian Army, led by Hussein's son, the Emir Feisal, and British liaison officer T. E. Lawrence, extended the revolt northwards. Finally, Lawrence and bedouin tribesmen won the Battle of Aqaba in July 1917. The capture of the port of Aqaba allowed the Allies to supply Feisal's forces and deprived the Ottomans of a position behind the right flank of the EEF.