After the defeat of the Japanese forces along the northern beaches of New Guinea at Buna, Gona, Salamaua and later Wau, the stage was set for the next phase of clearing Japanese forces from the north coast. Attention centred on Lae and the Huon Peninsula.
The plan for capture of Lae was to entail a pincer movement. The 9th Division was to make an amphibious landing east of the town and then advance upon it along the coast. Meanwhile the 7th Division would be flown into Nadzab in the Markham Valley and advance on Lae from the west. The 5th Division would continue its operations west of Salamaua to divert Japanese attention from Lae.
Extract from AWM 'Wartime' (see link in sidebar)
The New Guinea offensives of 1943–44 were the single largest series of connected operations Australia has ever mounted. While the supreme command was, of course, American and while the campaign depended upon American air and naval support, the New Guinea battles were Australia’s own. They involved tens of thousands of troops, both in combatant units and in the massive logistic infrastructure that jungle warfare demanded.
They involved units of all three Australian services. Though the common image of Australians in the New Guinea campaigns is of a soldier in jungle green, the RAN and RAAF provided vital support. The navy protected the convoys carrying men and supplies to New Guinea and often charted the coastline on which they landed. They involved vessels of all sizes, from the Fairmile launches raiding the Japanese-held coast to the big landing ships carrying the 9th Division into the amphibious landings near Lae. The RAAF, operating as part of the US Fifth Air Force, provided both direct air support against Japanese positions and carried men and supplies in and wounded out of the battle. Virtually every type operated by the RAAF took part in the campaigns, from Boomerang artillery spotters to the Beaufighters and Beauforts providing close support, and the Kittyhawks which protected them, and the Dakotas on which transport in the islands depended.