The 23rd Battalion was an infantry battalion of the Australian Army. It was raised in 1915 as part of the Australian Imperial Force for service during World War I and formed part of the 6th Brigade, attached to the 2nd Division. After being formed in Australia, the battalion was sent to Egypt to complete its training, before being committed to the Gallipoli Campaign as reinforcements in September 1915. They remained on the peninsula until the evacuation of Allied troops in December, when they were withdrawn back to Egypt where they were reorganised before being transferred to the Western Front in March 1916. Over the course of the next two-and-a-half years, the 23rd took part in a number of significant battles in France and Belgium, before being disbanded in mid-1919 following the conclusion of hostilities. In 1921, the battalion was re-raised as a part-time unit within the Citizens Forces in the state of Victoria, but was amalgamated with the 21st Battalion in 1929 to form the 23rd/21st Battalion.

The 6th Combat Support Brigade is an Australian Army brigade. First formed in 1912 as a Militia formation to provide training under the compulsory training scheme, the brigade was re-raised during the First World War as an infantry unit of the all volunteer Australian Imperial Force. It subsequently served at Gallipoli and in France and Belgium on the Western Front. In the 1920s, as part of a reorganisation of the Australian Army, it became part of the 3rd Military District of the Citizens Military Force, encompassing units from Victoria and South Australia. In 1991, it became part of the Ready Reserve Scheme, based at Enoggera Barracks, in Brisbane, Queensland, before being disbanded in 1996 when the scheme was discontinued. The brigade was re-raised on 1 March 2010 to oversee the Army's command support and intelligence, surveillance, target acquisition and reconnaissance units.