Key Facts
- Campaign start
- 19 September 1943
- Campaign end
- 24 April 1944
- Duration
- ~7 months
- Key terrain feature
- Shaggy Ridge, Finisterre Range
- Final objective captured
- Madang, 24 April 1944
Strategic Narrative Overview
Allied forces, primarily Australian troops supported by Australian and US aircraft, launched an offensive on 19 September 1943. Japanese units conducted a fighting withdrawal through the Markham and Ramu Valleys toward the Finisterre Range. The campaign's central confrontation occurred at Shaggy Ridge, a commanding north–south ridge within the Finisterres, where Australians launched assaults against entrenched Japanese positions in December 1943 and January 1944, eventually dislodging the defenders.
01 / The Origins
As part of the broader Allied New Guinea campaign in World War II, Allied forces sought to drive Japanese troops from the interior valleys of northeastern New Guinea. Control of the Markham and Ramu Valleys was strategically vital for advancing toward the Japanese-held northern coast. Japanese forces held a strong defensive line anchored in the rugged Finisterre Range, which dominated the region and posed a significant obstacle to Allied progress.
03 / The Outcome
Following their defeat at Shaggy Ridge, Japanese forces withdrew toward the northern coast of New Guinea. Australian and US troops pursued them through the Finisterres and along the coast from Saidor. Allied forces entered Madang on 24 April 1944, concluding the campaign. The Japanese continued their retreat to Wewak, where further fighting occurred through 1944 and 1945, as Allied pressure steadily compressed Japanese holdings in New Guinea.
Belligerents & Mobilization Analysis
Side A
2 belligerents
Side B
1 belligerent
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.