The 18th Indian Division was an infantry division of the British Indian Army that saw active service in the First World War. It took part in the Mesopotamian campaign and formed part of the occupation force for Iraq post-war. The division was not reformed for the Second World War.

The 9th Battalion, Middlesex Regiment was an infantry battalion of the British Army. Part of the Volunteer Force, later the Territorial Force, the battalion was part of the Middlesex Regiment and recruited from the north-western suburbs of London. It served as infantry in the Mesopotamian campaign during World War I and as an air defence regiment during and after World War II.