|New Britain, to the north-east of the New Guinea mainland, is approximately 500 kilometres long and averages 80 kilometres wide. Rabaul, in the north-east of the island, became the major Japanese logistics and operational base in the region. By early 1944, the island housed over 90,000 Japanese troops, including the 8th Area Army and the South-East Area Fleet. For much of the war, Rabaul and other areas of New Britain were subjected to prolonged Allied air raids.
The Japanese in New Britain occupied a defensive stance from September 1943. In December of that year, the Allies took control of the west of the island after landings by American forces at Cape Gloucester and on the south coast near Arawe. A series of decisive air victories left the Allies in control of the air and seas around New Britain after February 1944, effectively isolating the Japanese forces on the island.
While the American forces were content to secure and patrol their perimeters in the west of New Britain, Allied Intelligence Bureau (AIB) parties were active in gaining intelligence, assisting downed pilots and harrying Japanese troops. The 5th Australian Division relieved the American garrisons in October 1944 and adopted a more aggressive policy. By March 1945, the Australians had moved east along the north and south coasts to Open Bay and Wide Bay respectively, limiting Japanese movements to the Gazelle Peninsula.
New Britain units (Aust)
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