The sultan of Darfur Ali Dinar had been reinstated Change_of_leadership by the British after their victory Earnings_and_losses in the Mahdist War Military_operation but during the First World War Military_operation he grew Cause_change_of_position_on_a_scale restive , refusing Agree_or_refuse_to_act his customary tribute to the Sudanese government and showing Communication partiality Filling to the Ottoman Empire in 1915 .