 In the immediate post @-@ war period Australia contributed significant forces to the Allied occupation of Japan as part of the British Commonwealth Occupation Force ( <unk> ) , which included forces from Australia , Britain , India and New Zealand . At its height in 1946 the Australian component consisted of an infantry brigade , four warships and three fighter squadrons , totalling 13 @,@ 500 personnel . The Australian Army component initially consisted of the 34th Brigade which arrived in Japan in February 1946 and was based in <unk> Prefecture . The three infantry battalions raised for occupation duties were designated the 1st , 2nd and 3rd battalions of the Royal Australian Regiment in 1949 , and the 34th Brigade became the 1st Brigade when it returned to Australia in December 1948 , forming the basis of the post @-@ war Regular Army . From that time the Australian Army contribution to the occupation of Japan was reduced to a single under @-@ strength battalion . Australian forces remained until September 1951 when the <unk> ceased operations , although by the time the majority of units had been committed to the fighting on the Korean <unk> following the outbreak of the Korean War in 1950 . The RAAF component consisted of Nos. 76 , 77 and 82 Squadrons as part of No. 81 Wing RAAF flying P @-@ 51 Mustangs , initially based at <unk> from March 1946 , before transferring to <unk> in 1948 . However , by 1950 only No. 77 Squadron remained in Japan . A total of ten <unk> warships served in Japan during this period , including <unk> Ships Australia , Hobart , Shropshire , <unk> , <unk> , <unk> , Murchison , <unk> , <unk> and <unk> , while <unk> Ships <unk> , <unk> and <unk> also provided support . 
