The Australian Army is the principal land warfare force of Australia, a part of the Australian Defence Force (ADF) along with the Royal Australian Navy and the Royal Australian Air Force. The Army is commanded by the Chief of Army (CA), who is subordinate to the Chief of the Defence Force (CDF) who commands the ADF. The CA is also directly responsible to the Minister for Defence, with the Department of Defence administering the ADF and the Army.

The Australian Naval and Military Expeditionary Force (AN&MEF) was a small volunteer force of approximately 2,000 men, raised in Australia shortly after the outbreak of World War I to seize and destroy German wireless stations in German New Guinea in the south-west Pacific. The German wireless installations were ordered to be destroyed because they were used by Vizeadmiral Maximilian von Spee's East Asia Squadron of the Imperial German Navy, which threatened merchant shipping in the region. Following the capture of German possessions in the region, the AN&MEF provided occupation forces for the duration of the war. New Zealand provided a similar force for the occupation of German Samoa.