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war1945

1945 major battle of the Pacific War

January 1, 1945

The largest amphibious assault in the Pacific Theater, the Battle of Okinawa was the final major land battle before the planned invasion of Japan.

Quick Facts

Year
1945
Category
war

Key Facts

Duration
82 days (1 April – 22 June 1945)
Allied casualties
~50,000
Japanese casualties
~100,000
Okinawan civilian losses
at least 149,425 killed, missing, or coerced suicide
Allied assault force
U.S. Tenth Army: 4 Army + 3 Marine divisions
Japanese defenders
~100,000 troops, Thirty-Second Army

By the Numbers

82
Duration
50,000
Allied casualties
100,000
Japanese casualties
149,425
Okinawan civilian losses

Location

Map of Okinawa, JapanMap of Okinawa, JapanOkinawa, Japan

Cause → Event → Consequence

Cause

Following a prolonged island-hopping campaign across the Pacific, Allied planners required a staging base close to the Japanese home islands to launch Operation Downfall, the planned invasion of Japan. Okinawa, roughly 340 miles from Kyushu, was selected for its airfields and harbors, making its capture a strategic necessity in mid-1945.

Event

Operation Iceberg commenced on 1 April 1945 when U.S. Tenth Army forces landed on Okinawa in the largest amphibious assault in the Pacific Theater. For 82 days, American Army and Marine divisions fought Lieutenant General Mitsuru Ushijima's Japanese Thirty-Second Army across the island amid intense kamikaze attacks and brutal ground combat, earning the battle the name 'typhoon of steel.'

Consequence

The Allied victory secured Okinawa as a fleet anchorage and air base positioned close to Japan, and the extraordinary scale of casualties on both sides reinforced U.S. estimates of the cost of invading the Japanese home islands. The battle influenced the decision to use atomic bombs against Japan. The Japanese battleship Yamato was also sunk during the accompanying naval campaign.

Belligerents & Mobilization Analysis

Side A

1 belligerent

United States (Tenth Army: Army & Marine Corps)
Estimated Casualties~50K

Side B

1 belligerent

Imperial Japan (Thirty-Second Army)
Peak Mobilized Forces~100K
Estimated Casualties~100K
Casualty Rate100.0%
Forces vs Casualties ratio
0CasualtiesMobilized
Key Commanders

Mitsuru Ushijima.

Total Casualties (all sides)
150,000
Outcome
Allied (U.S.) victory; Okinawa secured as a staging base for the planned invasion of Japan

Timeline Context

Timeline around 194519451942194319441946194719481945 battle in the Eastern Front of World War IISecond World War battle from April 14-18, 1945Final World War II operations in Slovenia in May 1945.Treaty transferring territory between the United States and Soviet occupation zones of Germany after World War IIBorneo campaign — 1945 last major Allied campaign in the South West Pacific Area during World War IILasker Award — American medical science award2nd Golden Globe Awards — 1945 film award ceremony, on the 16th of April in Beverly Hills, California, United States of America, honoring achievements in 1944 filmmakingManila massacre — atrocities committed against Filipino civilians by Japanese troops at the Battle of Manilabattle-of-okinawa-1945