The 61st Battalion was an infantry battalion of the Australian Army. It was originally raised in 1917 during the First World War but was disbanded the same year without seeing active service. Later it was re-raised as a part of the Militia in 1938 in Brisbane, Queensland. Upon the outbreak of the Second World War they initially undertook garrison duties in Australia, however, in 1942 they were deployed to New Guinea where they took part in the Battle of Milne Bay, during which the Japanese were defeated for the first time in a major land battle. In late 1943, the 61st Battalion was withdrawn back to Australia for a period of re-organisation and training before being deployed overseas again in late 1944. This time they were deployed to Bougainville, where the Australian 3rd Division had taken over from the American garrison and the battalion joined the drive towards the Japanese stronghold at Buin in the south of the island. Following the end of the war, the 61st Battalion was disbanded as part of the demobilisation process on 8 January 1946.