in world war ii the islands near australia where a main battle was fought were the
The Japanese home island of Honshū.
Military history of Australia during World War II
ion from existing AIF personnel which would form part of the Commonwealth Corps with British, Canadian and New Zealand units. The corps' organisation was to be identical to that of a US Army corps, and it would have participated in the invasion of the Japanese home island of Honshū which was scheduled for March 1946. 
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Military history of Australia during World War II [SEP] Operations against the Japanese home islands
Planning for operations against Japan ceased in August 1945, when Japan surrendered following the atomic bombings of Hiroshima and Nagasaki. General Blamey signed the Japanese Instrument of Surrender on behalf of Australia during the ceremony held on board on 2 September 1945. Several RAN warships were among the Allied ships anchored in Tokyo Bay during the proceedings. Following the main ceremony on board "Missouri", Japanese field commanders surrendered to Allied forces across the Pacific Theatre. Australian forces accepted the surrender of their Japanese opponents at ceremonies conducted at Morotai, several locations in Borneo, Timor, Wewak, Rabaul, Bougainville and Nauru.