Battle of Okinawa - Dates & Conflict:
The Battle of Okinawa was fought from April 1 to June 22, 1945, during World War II (1939-1945).
Forces & Commanders
Battle of Okinawa - Background:
Having "island-hopped" across the Pacific, Allied forces sought to capture an island near Japan to serve as a base for air operations in support of the proposed invasion of the Home Islands. Assessing their options, the Allies decided to land on Okinawa in the Ryukyu Islands. Dubbed Operation Iceberg, planning began with Lieutenant General Simon B. Buckner's Tenth Army tasked with taking the island. The operation was scheduled to move forward following the conclusion of fighting on Iwo Jima. To support the invasion at sea, Admiral Chester Nimitz assigned Admiral Raymond Spruance's US Fifth Fleet (Map).
Battle of Okinawa - Allied Forces:
For the coming campaign, Buckner possessed nearly 200,000 men. These were contained in Major General Roy Geiger's III Amphibious Corps (1st & 6th Marine Divisions) and Major General John Hodge's XXIV Corps (7th & 96th Infantry Divisions). In addition, Buckner controlled the 27th and 77th Infantry Divisions, as well as the 2nd Marine Division. Having effectively eliminated the bulk of the Japanese surface fleet, Spruance's Fifth Fleet was largely unopposed at sea. As part of his command, he possessed Admiral Sir Bruce Fraser's British Pacific Fleet (BPF/Task Force 57).
Battle of Okinawa - Japanese Forces:
The defense of Okinawa was entrusted to General Mitsuru Ushijima's Thirty-Second Army. Numbering between 67,000 and 77,000 men, this formation was further supported by Rear Admiral Minoru Ota's 9,000 Imperial Japanese Navy troops at Oroku. To further augment his forces, Ushijima drafted nearly 40,000 civilians to serve as reserve militia and rear-echelon laborers. In planning his strategy, Ushijima intended to mount his primary defense in the southern part of the island and entrusted fighting at the northern end to Colonel Takehido Udo.
Battle of Okinawa - Campaign at Sea:
The naval campaign against Okinawa began in late March 1945, as the carriers of the BPF began striking Japanese airfields in the Sakishima Islands. Through the course of the battle, the British carriers proved highly resistant to kamikaze attacks due to their armored flight decks. The high point of the naval campaign came on April 7 when the Japanese launched Operation Ten-Go. This saw them attempt to run the battleship Yamato through the Allied fleet with the goal of beaching it on Okinawa for use a shore battery. Intercepted by Allied aircraft, Yamato was sunk shortly after leaving Japan.
As the land battle progressed, Allied naval vessels remained in the area and were subjected to a relentless succession of kamikaze attacks. Flying around 1,900 kamikaze missions, the Japanese sunk 36 Allied ships, mostly amphibious vessels and destroyers. An additional 368 were damaged. As a result of these attacks, 4,907 sailors were killed and 4,874 were wounded. Due to the protracted nature of the campaign, Spruance was relieved by Admiral William Halsey in late May and Allied naval forces were redesignated the Third Fleet.
Battle of Okinawa - Fighting Ashore:
Initial US landings began on March 26 when elements of the 77th Infantry Division captured the Kerama Islands to the west of Okinawa. On the 31st, Marines occupied Keise Shima. Only eight miles from Okinawa, the Marines quickly emplaced artillery on these islets to support future operations. The main assault moved forward against the Hagushi beaches on the west coast of Okinawa on April 1. This was supported by a feint against the southeast coast by the 2nd Marine Division. Coming ashore, Geiger and Hodge's men quickly swept across the south-central part of the island capturing the Kadena and Yomitan airfields (Map).
Having encountered light resistance, Buckner ordered the 6th Marine Division to begin clearing the northern part of the island. Proceeding up the Ishikawa Isthmus, they battled through rough terrain before encountering the main Japanese defenses on the Motobu Peninsula. Centered on the ridges of Yae-Take, the Japanese mounted a tenacious defense before being overcome on April 18. Two days earlier, the 77th Infantry Division landed on the island of Ie Shima offshore. In five days of fighting, they secured the island and its airfield.
Though fighting in the northern part of the island was concluded in fairly rapid fashion, the southern part proved a different story. Though he did not expect to defeat the Allies, Ushijima sought to make their victory as costly as possible. To this end, he had constructed elaborate systems of fortifications in the rugged terrain of southern Okinawa. Pushing south, Allied troops fought a bitter battle to capture Cactus Ridge on April 8, before moving against Kakazu Ridge. Forming part of Ushijima's Machinato Line, the ridge was a formidable obstacle and an initial American assault was repulsed (Map).
Counterattacking, Ushijima sent his men forward on the nights of April 12 and 14, but was turned back both times. Reinforced by the 27th Infantry Division, Hodge launched a massive offensive on April 19. In five days of brutal fighting, US troops forced the Japanese to abandon the Machinato Line and fall back to a new line in front of Shuri. As much of the fighting in the south had been conducted by Hodge's men, Geiger's divisions entered the fray in early May. On May 4, Ushijima again counterattacked, but heavy losses caused him to halt his efforts the next day.
Making skillful use of caves, fortifications, and the terrain, the Japanese clung to the Shuri Line limiting Allied gains and inflicting high losses. Much of the fighting centered on heights known as Sugar Loaf and Conical Hill. In heavy fighting between May 11 and 21, the 96th Infantry Division succeeded in taking the latter and flanking the Japanese position. Taking Shuri, Buckner pursued the retreating Japanese but was hampered by heavy monsoon rains. Assuming a new position on the Kiyan Peninsula, Ushijima prepared to make his last stand. While troops eliminated the IJN forces at Oroku, Buckner pushed south against the new Japanese lines. By June 14, his men had begun to breach Ushijima's final line along the Yaeju Dake Escarpment.
Compressing the enemy into three pockets, Buckner sought to eliminate enemy resistance. On June 18, he was killed by enemy artillery while at the front. He was ultimately replaced by General Joseph Stilwell. On June 21, the island was declared secure, though fighting lasted another week as the last Japanese forces were mopped up. Defeated, Ushijima committed hara-kiri on June 22.
Battle of Okinawa - Aftermath
One of the longest and costliest battles of the Pacific Theater, Okinawa saw American forces sustain 49,151 casualties (12,520 killed), while the Japanese incurred 117,472 (110,071 killed). In addition, 142,058 civilians became casualties. Though effectively reduced to a wasteland, Okinawa quickly became a key military asset for the Allies as it provided a key fleet anchorage and troop staging areas. In addition, it gave the Allies airfields that were only 350 miles from Japan.