Many of the division's units transferred directly from India so time was needed for them to become acclimatized.

It remained in Mesopotamia for the rest of the First World War, taking part in the action at Fat-ha Gorge on the Little Zab (23–26 October 1918) and the Battle of Sharqat (28–30 October 1918) under the command of I Corps.

[2][3] At the end of the war, the 18th Division was chosen to form part of the occupation force for Iraq.

It took part in the Iraq Rebellion in 1920 and was broken up in the following year.

Fanshawe[6] and from 12 March 1919 by Major-General Theodore Fraser.