Battle of Okinawa

The Battle of Okinawa (Japanese: 沖縄戦, Hepburn: Okinawa-sen), codenamed Operation Iceberg,^: 17 was a major battle of the Pacific War fought on the island of Okinawa by United States Army and United States Marine Corps forces against the Imperial Japanese Army. The initial invasion of Okinawa on 1 April 1945 was the largest amphibious assault in the Pacific Theater of World War II. The Kerama Islands surrounding Okinawa were preemptively captured on 26 March 1945 by the U.S. Army 77th Infantry Division. The 82-day battle on Okinawa lasted from 1 April 1945 until 22 June 1945. After a long campaign of island hopping, the Allies were planning to use Kadena Air Base on the island as a staging point for Operation Downfall, the planned invasion of the Japanese home islands, 340 mi (550 km) away.

The United States created the Tenth Army, a cross-branch force consisting of the U.S. Army 7th, 27th, 77th and 96th Infantry Divisions with the 1st, 2nd, and 6th Marine Divisions, to seize the island. The Tenth Army was unique because it had its own Tactical Air Force (joint Army-Marine command) and was supported by combined naval and amphibious forces. Opposing the Allied forces on the ground was the Japanese Lieutenant General Mitsuru Ushijima's Thirty-Second Army, a mixed force consisting of regular army troops, naval infantry and conscripted local Okinawans. Total Japanese troop strength on the island was about 100,000 at the onset of the invasion. The Battle of Okinawa was the single longest sustained carrier campaign of the Second World War.

The battle has been referred to as the "typhoon of steel" in English, known in Japanese as "tetsu no bōfū". The nicknames refer to the ferocity of the fighting, the intensity of Japanese kamikaze attacks and the sheer numbers of Allied ships and armored vehicles that assaulted the island. The battle was the bloodiest and fiercest in the Pacific Ocean Theatre, with some 50,000 Allied and around 100,000 Japanese casualties,^{: 473–474} also including local Okinawans conscripted into the Japanese Army. According to local authorities, at least 149,425 Okinawan people were killed, died by coerced suicide or went missing.

In the naval operations surrounding the battle, both sides lost considerable numbers of ships and aircraft, including the Japanese battleship Yamato. After the battle, Okinawa provided the victorious Allies with a fleet anchorage, troop staging areas, and airfields in close proximity to Japan as they planned to invade the Japanese home islands.