A component of the Salamaua–Lae campaign in which U.S. infantry struggled for weeks to dislodge Japanese forces from a fortified coastal ridge in New Guinea.
Key Facts
- Start date
- 21 July 1943
- End date
- 14 August 1943
- Duration
- Approximately 25 days
- U.S. unit engaged
- 162nd Infantry Regiment
- Named after
- A U.S. battalion commander surnamed Roosevelt
- Campaign context
- Salamaua–Lae campaign, Territory of New Guinea
By the Numbers
Location
Cause → Event → Consequence
Throughout 1943, Allied forces pushed Japanese troops back from Wau and Mubo toward Salamaua. After a U.S. landing at Nassau Bay in early July, American troops advanced north along the coast. By mid-July they encountered a heavily defended Japanese position overlooking Tambu Bay, which became known as Roosevelt Ridge, named for a U.S. battalion commander.
Between 21 July and 14 August 1943, the U.S. 162nd Infantry Regiment launched repeated assaults on Roosevelt Ridge. Progress was slow against entrenched Japanese defenders, and the drawn-out fighting strained relations between U.S. and Australian commanders due to inter-Allied service politics before the ridge was finally captured in mid-August.
The capture of Roosevelt Ridge in mid-August 1943 advanced the Allied push toward Salamaua as part of the broader Salamaua–Lae campaign. The protracted struggle exposed tensions between U.S. and Australian commanders, while the ridge's fall contributed to weakening the Japanese defensive perimeter around Salamaua and Lae.
Belligerents & Mobilization Analysis
Side A
2 belligerents
Side B
1 belligerent