The Japanese convoy was a result of a Japanese Imperial General Headquarters decision in December 1942 to reinforce their position in the South West Pacific. A plan was devised to move some 6,900 troops from Rabaul directly to Lae. The plan was understood to be risky, because Allied air power in the area was strong, but it was decided to proceed because otherwise the troops would have to be landed a considerable distance away and march through inhospitable swamp, mountain and jungle terrain without roads before reaching their destination. On 28 February 1943, the convoy – comprising eight destroyers and eight troop transports with an escort of approximately 100 fighter aircraft – set out from Simpson Harbour in Rabaul.