When General Sir Edmund Allenby took over command of the Egyptian Expeditionary Force (EEF) in Palestine in the Summer of 1917, he completely reorganised it.

[4] XXI Corps Headquarters was formed on 12 August at Deir al-Balah to take responsibility for the left section of the EEF's line in front of Gaza City, including 52nd (Lowland), 54th (East Anglian) and 75th Divisions and three brigades of heavy artillery.

[10] Major-General Edward Bulfin of 60th (2/2nd London) Division was promoted to Lieutenant-General to command the new formation, which was built up during the late summer for the resumption of the offensive in October.

XXI Corps was ordered to pursue vigorously and capture Wadi el Hesi before the Turks could occupy the strong position there.

[14][15][16] The advance then continued and XXI Corps was involved in the following actions:[6] Following the German Spring Offensive on the Western Front in March 1918, the EEF was obliged to send reinforcements to the British Expeditionary Force.

XXI Corps, with five infantry divisions and a cavalry brigade, had the task of breaking through Turkish trench lines that in places were5 miles (8.0 km) deep.

The Official History described the part played by XXI Corps in the battle as 'one of the most overwhelmingly successful operations of the war', and praised the staff for their efforts to supply water as the advance progressed.

Extensive engineering work would be required to make it passable for wheeled vehicles, with the danger of the whole cliff shelf falling into the sea.

Before it was completed, XXI Corps Cavalry Regiment advanced cross-country on 4 October and entered Tyre, where the Royal Navy landed supplies for the columns.