HistoryData
Historical Conflict

Battle of Lone Tree Hill

U.S. capture of Lone Tree Hill secured Maffin Bay as a staging base for six subsequent Allied amphibious operations across the Pacific.

Duration & Scope

1944 ongoing

< 1 year

Estimated Total Casualties

2K

Key Facts

Duration
17 May – 2 September 1944 (~3.5 months)
Japanese dead
more than 1,000
U.S. battle casualties
~700 battle, ~500 non-battle
Hill height
175 ft (53 m)
Remaining Japanese troops (1 Sep)
~2,000

Strategic Narrative Overview

The 158th RCT engaged the entrenched Japanese forces beginning 17 May 1944, facing fierce resistance in dense jungle and fortified caves on the coral formation. On 14 June, General Walter Krueger committed the U.S. 6th Infantry Division to relieve the 158th RCT. After ten days of intense fighting, American forces seized the hill, collapsing caves and killing a large number of defenders. Scattered Japanese resistance continued in the surrounding area through late summer.

01 / The Origins

Following the Allied landings at Hollandia and Aitape in late April 1944, the Toem-Wakde-Sarmi coastal salient became an isolated Japanese position in Dutch New Guinea. Elements of the Japanese 223rd and 224th Infantry Regiments concentrated on Lone Tree Hill overlooking Maffin Bay, blocking the U.S. 158th Regimental Combat Team from advancing toward Sarmi. The Japanese held well-fortified cave positions while their 223rd Regiment outflanked American units.

03 / The Outcome

By 1 September 1944, roughly 2,000 Japanese troops remained in the area but were no longer capable of threatening Allied operations. With Lone Tree Hill secured, Maffin Bay was developed into a major staging base used to support six subsequent Allied operations, including Biak, Noemfoor, Sansapor, Leyte, and Luzon, significantly accelerating the Western New Guinea campaign's momentum.

Belligerents & Mobilization Analysis

Side A

1 belligerent

United States Army
Estimated Casualties~1K
Key Commanders

Walter Krueger.

Side B

1 belligerent

Imperial Japanese Army
Estimated Casualties~1K
Key Commanders

Hachiro Tagami.

Total Casualties (all sides)
2,200
Outcome
U.S. victory; Lone Tree Hill captured; Maffin Bay secured as Allied staging base

Kinetic Engagement Axis

Major engagements timeline (1944–present)Timeline of major military engagements plotted chronologically.1944present1944Attack on Sawar …Allied1944Wakde Island ass…Allied1944Battle of Lone T…Allied

Scroll horizontally to view full axis. Events plotted relatively.

Side A victorySide B victoryInconclusiveDecisive / turning point

Location

Map of Maffin Bay, Dutch New GuineaMap of Maffin Bay, Dutch New GuineaMaffin Bay, Dutch New Guinea