Okinawa Campaign Meets Stiff Japanese Resistance Summary

  • Last updated on November 10, 2022

The last major battle of World War II began with the largest amphibious invasion in history. The bloodiest campaign in the Pacific theater, it cost more than 250,000 Japanese and Okinawans and nearly 13,000 Allied troops their lives. The carnage presaged what would happen in an invasion of the Japanese homeland and was influential in the decision to drop atomic bombs on Japan.

Summary of Event

On the day the Battle of Iwo Jima was declared over and that island secured, March 26, 1945, Allied military forces began their invasion of the Ryukyu Islands, a chain of islands stretching southwest between the Japanese island of Kyūshū and Formosa (Taiwan). The invasion began on the tiny Kerama Islands, at the southwestern end of the chain. Okinawa, Battle of (1945) Operation Iceberg World War II (1939-1945)[World War 02];Japanese campaign [kw]Okinawa Campaign Meets Stiff Japanese Resistance (Apr. 1-July 2, 1945) [kw]Campaign Meets Stiff Japanese Resistance, Okinawa (Apr. 1-July 2, 1945) [kw]Japanese Resistance, Okinawa Campaign Meets Stiff (Apr. 1-July 2, 1945) [kw]Resistance, Okinawa Campaign Meets Stiff Japanese (Apr. 1-July 2, 1945) Okinawa, Battle of (1945) Operation Iceberg World War II (1939-1945)[World War 02];Japanese campaign [g]Asia;Apr. 1-July 2, 1945: Okinawa Campaign Meets Stiff Japanese Resistance[01440] [g]Japan;Apr. 1-July 2, 1945: Okinawa Campaign Meets Stiff Japanese Resistance[01440] [c]Military history;Apr. 1-July 2, 1945: Okinawa Campaign Meets Stiff Japanese Resistance[01440] [c]World War II;Apr. 1-July 2, 1945: Okinawa Campaign Meets Stiff Japanese Resistance[01440] [c]Wars, uprisings, and civil unrest;Apr. 1-July 2, 1945: Okinawa Campaign Meets Stiff Japanese Resistance[01440] Buckner, Simon Bolivar, Jr. Cho, Isamu Geiger, Roy S. Spruance, Raymond A. Ugaki, Matome Ushijima, Mitsuru Yahara, Hiromichi

Fifteen miles east of the Keramas lay the Allies’ main goal: Okinawa. Okinawa, annexed by Japan in 1879, was defended by approximately ninety thousand Japanese troops and twenty thousand Okinawan conscripts under the command of Lieutenant General Mitsuru Ushijima. The Allies wanted Okinawa as a base for a projected invasion of Japan; the Japanese, despite their condescending attitude toward the Okinawans, considered the island Japanese soil and were determined to fight to the last man to defend it.

Operation Iceberg, the invasion of Okinawa, utilized the largest invasion armada in history: 1,600 ships under the command of Admiral Raymond A. Spruance, and 545,000 U.S. Army and Marine Corps soldiers commanded by Lieutenant General Simon Bolivar Buckner, Jr. The attack force of approximately of 184,000 men landed near the midpoint of Okinawa on April 1, 1945, which was both April Fools’ Day and Easter Sunday. It seemed like a joke and a blessing when the landings were largely unopposed, and “L Day” (the L stood for “landing”) was soon called “Love Day” by the American invaders. For the next few days, objectives such as the capture of the Yontan and Kadena airfields were easily attained, and the burning question on the minds of Marines heading north and Army solidiers heading south was, “Where are the Japanese?”

General Ushijima, his forces weakened by the transfer of twenty-five thousand troops to Formosa and the loss of fifty-six hundred soldiers in the sinking of the troop transport Toyama Maru, Toyama Maru (ship) decided to wage jikyusen, a defensive war of attrition, using the rugged terrain of Okinawa to greatest advantage. Accordingly, he sent two thousand men to fight in the mountainous territory of the northern Motobu Peninsula, while marshaling his main strength in an intricately fortified system of caves and tunnels in the southern portion of Okinawa. This defensive position, known as the Shuri line Shuri line after its headquarters in Shuri Castle, bisected the island and was set to become a death trap for the advancing infantrymen.





A death trap of a different nature was planned for the Allied fleet. Vice Admiral Matome Ugaki had gathered thousands of planes on Kyūshū to use in kamikaze (suicide) assaults on Allied ships. On April 6, while American troops were still traversing Okinawa largely unopposed, Ugaki unleashed the largest suicide attack in history: 355 planes and 10 ships, including the largest battleship in the world, the Yamato. The Yamato Yamato (ship) and most of its escort were sunk before reaching Okinawa, but kamikazes Kamikaze attacks sank ten American ships and damaged several others in an attack that lasted two days. Ugaki would launch nine other kamikaze sorties—known as kikusi, or “floating chrysanthemums”—during the succeeding months of the Okinawa campaign.

On April 8, the Americans “found” the Japanese. In the north, the Marines engaged two thousand Japanese soldiers holed up around Mount Yaetake on Motobu Peninsula. The Marines battled their way to the summit of the mountain, reaching it and ending organized resistance on Motobu on April 18. In the south, the Army’s advance was halted by withering fire at Kakazu Ridge and other strongholds in the outer defensive ring of the Shuri line. Several American assaults on these defenses over the next few days were repulsed with heavy casualties. A Japanese counterattack (April 12-13) was crushed, but fighting in the south was effectively stalemated.

The Americans launched a major offensive on the Shuri line on April 19. Bitter fighting, often hand-to-hand combat, raged as the Americans used tactics such as, in the words of Buckner, “corkscrew” (explosives) and “blowtorch” (flamethrowers and napalm) in trying to dislodge the tenacious Japanese defenders. The offensive was initially halted, but within the next few days U.S. soldiers had begun to penetrate the Shuri line’s outer defenses. Ushijima ordered his troops to withdraw to the inner core of the Shuri line on April 23.

Meanwhile, three days before the main body of U.S. troops began their offensive against the Shuri line, two regiments of infantrymen landed on Ie Shima, 3.5 miles west of Motobu Peninsula. In six days of brutal fighting, they killed nearly five thousand Japanese troops and gained control of a valuable airfield. However, American military personnel also lost their beloved war correspondent, Ernie Pyle Pyle, Ernie , to a Japanese machine gun on April 18.

The month of May began with renewed efforts by the Army, reinforced by the Marines, to crack the Shuri line. The Japanese held on tenaciously, but Ushijima was to make a decision that would doom the Shuri line defenders. Lieutenant General Isamu Cho, Ushijima’s fiery chief of staff, argued for a major counterattack against the Americans. Colonel Hiromichi Yahara, Ushijima’s brilliant strategist and the primary advocate of a war of attrition, objected, but Ushijima sided with Cho and ordered an attack for May 3.

In spite of being coordinated with one of the largest Japanese artillery bombardments of the war and a kikusi to provide it cover, the attack was a disastrous failure. The Japanese lost more than six thousand troops, numerous artillery pieces, and a significant amount of irreplaceable ammunition. A week later, in the midst of seventeen days of torrential rain that turned Okinawa into a mire of mud and decaying flesh, the Marines in the west and the Army in the east attacked the flanks of the now weakened Shuri line. Ushijima, realizing that his defenses were crumbling, ordered a retreat to the southernmost part of Okinawa, setting up a final stand in the rugged terrain of Yake-Dake and Yuza-Dake. The Marines captured Shuri Castle on May 29.

By mid-June, the Marines had annihilated several thousand Japanese naval troops on Oroku Peninsula, and Ushijima’s last defenses were crumbling. On June 17, Ushijima’s army collapsed into unorganized pockets of soldiers willing to fight to the death and, unlike in other Pacific battles, scores of Japanese ready to surrender. General Buckner did not witness the final victory, however; he was killed by Japanese artillery fire on June 15. Marine Major General Roy S. Geiger took over command of American forces—becoming the first Marine to command an army—and declared victory on June 21. Generals Ushijima and Cho committed ritual suicide the next day. One-sided fighting continued, however, for the next week, as a mop-up of the scattered remnants of Ushijima’s army yielded approximately nine thousand Japanese dead and four thousand prisoners. The Battle of Okinawa was officially ended on July 2.


The Okinawan campaign exacted a staggering toll on the combatants and the Okinawan civilians caught in the midst of the carnage. The Japanese battle casualties were roughly 100,000 dead and 10,000 prisoners (including unarmed laborers). The loss of sixteen ships essentially ended Japan’s navy, and its air force was greatly weakened by the loss of some three thousand planes (far fewer than the original Allied estimate of seventy-eight hundred).

American ground casualties were the highest for any campaign against the Japanese: 49,151 men, of whom 12,500 were killed. U.S. naval losses in ships—36 sunk, 368 damaged—and men—approximately 5,000 killed and the same number wounded—were the worst in American naval history for one campaign. The Okinawans suffered most of all: An estimated 150,000, approximately one-third of the pre-invasion population, died during the gory engagement. Additionally, the opposing commanders were the two highest-ranking officers to die during one World War II battle.

The horror that was Okinawa convinced the U.S. High Command that an invasion of Japan would be a bloodbath of unprecedented proportions. Undoubtedly, the Okinawa campaign played a major role in President Harry S. Truman’s decision to drop two atomic bombs on Japanese cities. Okinawa, Battle of (1945) Operation Iceberg World War II (1939-1945)[World War 02];Japanese campaign

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Appleman, Roy E., James M. Burns, Russell A. Gugelar, and John Stevens. Okinawa: The Last Battle. Washington, D.C.: U.S. Army Center for Military History, 1948. Written by combat historians who participated in the Okinawa campaign, this book presents a comprehensive account of the battle. Numerous maps, charts, tables, and black-and-white photographs.
  • citation-type="booksimple"

    xlink:type="simple">Feifer, George. Tennozan: The Battle for Okinawa and the Atomic Bomb. New York: Ticknor and Fields, 1992. The horror of Okinawa is brought to life through a focus on the personal experiences of three participants: a Marine, a Japanese soldier, and an Okinawan. Black-and-white photographs.
  • citation-type="booksimple"

    xlink:type="simple">Leckie, Robert. Okinawa: The Last Battle of World War II. New York: Viking, 1995. Good introductory read emphasizing the perspective of the average combatant. Black-and-white photographs.
  • citation-type="booksimple"

    xlink:type="simple">Sledge, Eugene B. With the Old Breed: At Peleliu and Okinawa. Annapolis, Md.: Naval Institute Press, 1996. A Marine veteran’s highly acclaimed memoir provides a riveting, brutally honest account of the lives of Marines during two horrific battles. Black-and-white photographs, maps.
  • citation-type="booksimple"

    xlink:type="simple">Yahara, Hiromichi. The Battle for Okinawa. New York: Wiley, 1995. Eyewitness account of the Okinawa campaign from inside Japanese headquarters by one of the Japanese army’s chief strategists. Black-and-white photographs.

World War II: Pacific Theater

Japan Invades the Philippines

Central Pacific Offensive

Battle of the Philippine Sea

Japan Orders Kamikaze Attacks

American Flag Is Raised at Iwo Jima

War Correspondent Pyle Dies in Combat

Atomic Bombs Destroy Hiroshima and Nagasaki

Categories: History