[2] It was initially led by the Irish Lieutenant General Sir Bryan Mahon and fought at Gallipoli in 1915, Salonika, from 1915–1917, and Palestine from 1917–1918.
In September 1915, when the Suvla front became a stalemate, the division was moved to Salonika where it remained for almost two years and fought the Battle of Kosturino.
The division moved to Egypt in September 1917 where it joined Lieutenant General Sir Philip Chetwode's XX Corps.
It fought in the Third Battle of Gaza which succeeded in breaking the resistance of the Turkish defenders in southern Palestine.
Heavy losses on the Western Front following Operation Michael, the great German spring offensive in 1918, resulted in the transfer of ten of the division's battalions from Palestine to France, their place being taken by Indian Army units.