22 April – 16 September 1943

Japanese moves against Wau, indeed any offensive action by the enemy in New Guinea, became impossible after Allied aircraft destroyed a major Japanese naval troop convoy at the Battle of the Bismarck Sea (2 – 4 March 1943).

Australian Militia units flown into Wau joined battle-hardened troops of Kanga Force to form the 3rd Division. These troops pushed through mountainous jungle towards enemy-held Salamaua and occupiedLababia Ridge in mid-March 1943, before clashing with the Japanese at Mubo on 22 April.

In early May, the 2/7th Battalion attacked ‘The Pimple’ and ‘Green Hill’ – strong enemy positions – but made little progress. 2/3rd Independent Company commandos, however, triumphed at Bobdubi Ridge. The hard-pressed Japanese brought in reinforcements from Finschhafen and launched a counterattack against Lababia Ridge (20 - 23 June). The Australian defenders held firm.

Green militiamen of the 58/59th Infantry Battalion, supported by 2/3rd Independent Company veterans, swept the formidable Bobdubi Ridge and Old Vickers positions between 30 June and 19 August 1943 and opened the route to Salamaua. American soldiers landing at Nassau Bay fought their way inland to support Australian attacks on Mt Tambu (16 July – 19 August).

Fierce jungle fighting served to draw the Japanese away from formidable prepared positions at Salamaua andLae. The garrisons were fatally weakened and when Allied troops landed near Lae, in the first week of September, the enemy withdrew north. Australian troops occupied Salamaua on 11 September and Lae on 16 September. Finschhafen fell two weeks later.