Originally raised as a militia formation in 1912, the 5th Brigade was re-raised for overseas service in 1915 as part of the Australian Imperial Force during the First World War.

Following the war, the brigade was re-raised in 1948 once again and it is currently a Reserve combined arms formation based in New South Wales and forms part of the 2nd Division.

[2] Following the outbreak of the First World War, the 5th Brigade was re-raised in mid-1915 as part of the Australian Imperial Force (AIF) from volunteers for overseas service.

[3] Assigned to the 2nd Division, the majority of its personnel were drawn from men that had previously served in New Guinea with the Australian Naval and Military Expeditionary Force.

[4] After formation, the brigade departed Australia, embarking for Egypt, in May 1915, and after a period of training, were dispatched to Gallipoli in August as reinforcements for the 1st Division, which had been there since April.

After the offensive failed, the 5th Brigade remained at Gallipoli, undertaking mainly defensive tasks until they were evacuated in December 1915 and withdrawn back to Egypt.

These plans were not enacted and the brigade was disbanded in June 1944 as part of the reallocation of manpower and resources undertaken by the Army at the time to reinforce operational units that were already deployed.