By late 1943 and early 1944, Australian and US forces had begun offensive actions in New Guinea, having stemmed the tide of the Japanese advance during the fighting in 1942.
Against this, the Australian forces were drawn from the 7th Division, which due to limited resources only pushed two brigades forward at any one time; initially these were the 21st and 25th Brigades, although they were later replaced by the 15th and 18th Brigades.