The majority of Australian units in the Mediterranean returned to Australia in early 1942 , after the outbreak of the Pacific War . The 9th Division was the largest unit to remain in the Middle East , and played a key role in the First Battle of El Alamein during June and the Second Battle of El Alamein in October . The division returned to Australia in early 1943 , but several RAAF squadrons and RAN warships took part in the subsequent Tunisia Campaign and the Italian Campaign from 1943 until the end of the war .