At the start of the Pacific War the strategic port town of Rabaul in New Britain was defended by 'Lark Force', which comprised the 2/22nd Infantry Battalion reinforced with coastal artillery and a poorly equipped RAAF bomber squadron. While Lark Force was regarded as inadequate by the Australian military, it was not possible to reinforce it before the Japanese South Seas Force landed at Rabaul on 23 January 1942. The outnumbered Australian force was swiftly defeated and most of the survivors surrendered in the weeks after the battle. Few members of Lark Force survived the war, as at least 130 were murdered by the Japanese on 4 February, and 1,057 Australian soldiers and civilian prisoners from Rabaul were killed when the ship carrying them to Japan () was sunk by the US submarine on 1 July 1942.