Markham, Ramu and Finisterre campaigns

The Markham Valley, Ramu Valley and Finisterre Range campaigns were a series of battles within the broader New Guinea campaign of World War II. The campaigns began with an Allied offensive in the Ramu Valley, from 19 September 1943, and concluded when Allied troops entered Madang on 24 April 1944. During the campaign, Australian forces – supported by Australian and US aircraft – advanced through the Markham Valley and Ramu Valleys during which there were minor clashes with Japanese forces, which withdrew towards their main defensive line in the Finisterre Range. A central geographical and strategic feature of these campaigns was the imposing Shaggy Ridge, running north–south in the Finisterres; this was the scene of a climactic battle during which the Australians assaulted the Japanese positions in December 1943 and January 1944. Following the fighting around Shaggy Ridge, the Japanese withdrew towards the northern coast of New Guinea, where they were pursued by Australian and US forces advancing through the Finisterres and along the coast from Saidor. Following the capture of Madang, the Japanese eventually withdrew to Wewak where further fighting took place in 1944 and 1945. During September 1943, Australian forces from Major General George Vasey's 7th Division, advancing from Nadzab, had captured Lae, as part of a pincer undertaken in conjunction with Major General George Wootten's 9th Division, which had advanced along the coast from the east of Lae. Heavy rain had held up the Australian advance and much of the garrison had managed to withdraw inland, prior to the capture of the town. To follow these forces up, the 9th Division's focus then shifted to the Huon Peninsula, while the 7th Division – following the capture of Kaiapit – advanced from there to Dumpu and Marawasa, to prepare for the Australian advance through the Ramu Valley and into the Finisterre Range, towards Bogadjim near Madang on the northern coast. The Japanese formation in the campaign was the Nakai Detachment, a brigade-sized formation detached from the Japanese 20th Division under Major General Masutaro Nakai.