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Japan Surrenders and World War II Ends: June 1945-September 1945

World War II Timeline: July 23, 1945-July 30, 1945
Photo courtesy Legacy Publishers

Nazi war crimes trials were underway in July 1945. The World War II timeline below summarizes these and other important events in July of 1945.

World War II Timeline: July 23-July 30

July 23: The trial of Nazi collaborator Marshal Philippe P├ętain begins at Paris' Palais de Justice.

July 24: The USAAF raids the densely populated Japanese cities of Osaka and Nagoya with some 600 B-29 bombers.

July 26: Truman, Attlee, and Stalin issue a statement from Potsdam warning the Japanese that they face "utter destruction" if they do not surrender unconditionally. Tokyo will reject the ultimatum within the week.

The USS Indianapolis delivers critical atomic bomb components to the bombing base at Tinian.

The Labour Party takes power in Britain, forcing out Conservative Winston Churchill. He will be replaced at Potsdam by the new prime minister, Clement Attlee, on the 27th.

July 27: The USAAF drops some 600,000 leaflets over 11 Japanese cities, warning civilians of probable air raids.

July 28: More than a dozen people die when a B-25 bomber pilot becomes disoriented in heavy fog and crashes into New York's Empire State Building.

Japan's kamikaze pilots sink their last Allied ship, as the USS Callaghan goes down off Okinawa.

More than 13,000 Japanese troops die, either from hostile fire or drowning, in an attempt to retreat over Burma's Sittang River.

July 29-30: The USS Indianapolis goes down after being struck by two torpedoes fired from a Japanese submarine. A series of operational errors will delay rescue for days, by which time three-quarters of the crew will perish, many from shark attacks.

July 30: The Japanese government instructs its civilian population to collect acorns to stave off starvation.

World War II Headlines

Below are more highlights and images that outline the events of World War II, including the first atomic explosion.

The first atomic explosion is a test in the New Mexican desert: On July 16, 1945, a plutonium-core nuclear bomb was raised to the top of a 65-foot-high steel tower in the New Mexican desert about 30 miles southeast of Socorro. The Trinity test began when the bomb, called "the gadget," was detonated on July 16 at 5:30 a.m. The scientists, watching 10 miles from the tower, had disagreed on what would happen following the detonation -- from nothing to the end of the world. Instead it caused an explosion that was about the equivalent of 19 kilotons of TNT. The flash it created brightened the surrounding mountains and emitted a mushroom cloud about eight miles high.

Harry Truman and Allied leaders attend the Potsdam Conference: President Harry Truman had his first and only meeting with the other Allied leaders, Winston Churchill and Joseph Stalin, in Potsdam, Germany, from July 17 to August 2, 1945. Churchill left before the conference ended because his party had lost the British general election; he was replaced by Clement Attlee. The Potsdam agreements clarified major postwar issues for Germany and Poland. The Potsdam Declaration called for Japan to surrender unconditionally or face complete destruction.

Crew members killed by sharks after sinking of the Indianapolis: Medical personnel tend to sailors from the USS Indianapolis who survived days in the water after the heavy cruiser was sunk by a Japanese submarine. Indianapolis, returning after delivering atomic bomb parts to Tinian, went down in 12 minutes on July 30, 1945. Though the ship was overdue at Leyte, no alert was issued. The survivors were accidentally spotted by a patrol aircraft on August 2. Of the 1,196 crew members, all but 317 died, many of them killed by sharks. In a remarkable miscarriage of justice, the Navy placed blame for the disaster on the ship's captain, Charles McVay, charging him with "failing to zig-zag."

President Harry Truman's approval for the atomic attacks: A handwritten note by President Harry Truman approves the wording of a statement he plans to issue after the first atomic bomb is dropped on Japan. Sent in reply to a cable from Secretary of War Henry Stimson, the message reads, "Release [the statement] when ready but not sooner than August 2." The Allies' demand for unconditional surrender, sent to Japan on July 26, 1945, was rejected. The U.S. had successfully tested an A-bomb in mid-July, so by the end of the month Truman knew that at least one of the two A-bombs that remained would be dropped on Japan, sooner rather than later.

Preparation for the atomic bomb attack on Hiroshima and Nagasaki: The selection of potential atomic bomb targets began even before the Trinity test bomb was detonated near Alamogordo, New Mexico, on July 16, 1945. The Target Committee at Los Alamos recommended Hiroshima as a likely target as early as May. By late July, the list of potential targets included four cities: Hiroshima, Kokura, Kyoto, and Niigata. Kyoto was later dropped from the list due to its significance as a cultural center. Nagasaki took Kyoto's place. Hiroshima remained the primary target, followed by Kokura and Nagasaki. Each city had military facilities of some type. Hiroshima was a headquarters and logistics base; Kokura had a large munitions plant; Nagasaki had various arms factories.

Of equal importance, these sprawling urban areas did not require precision bomb drops and would vividly demonstrate the destructiveness of the new weapons. Civilian casualties were not an issue. This was total war, and civilian populations were considered a legitimate target in the effort to break Japan's will to fight. At 8:15 a.m. on August 6, 1945, the B-29 Superfortress Enola Gay dropped a U-235 bomb nicknamed "Little Boy" on the primary target, Hiroshima. The resulting blast instantly killed upwards of 80,000 people and damaged or destroyed 90 percent of the city's buildings.

Three days later, the B-29 Bock's Car, carrying the plutonium bomb "Fat Man," aborted over its primary target, Kokura, due to heavy cloud cover. Bock's Car proceeded to Nagasaki, its secondary target, and dropped the second atomic bomb of the war shortly after 11 a.m. About 25,000 people were instantly killed. On August 15, Japan capitulated.The morality of the bombings has been passionately debated. Critics maintain that Japan was already near surrender; that the bombs were intended primarily as a warning to the Russians; and that racism was a motivating factor. Proponents argue that the bombings saved hundreds of thousands of American lives--and, in the long term, perhaps millions of Japanese as well--by forcing a speedy surrender.

Colonel Paul Tibbets in charge of A-bomb drop: The Enola Gay was the B-29 that carried the atomic bomb in the attack on Hiroshima. Colonel Paul Tibbets spent months organizing and training the 509th Composite Group to meet the unique challenges of dropping atomic bombs, all with no assurance that the mission would actually take place. The successful bomb test in New Mexico in July 1945, followed by Japan's rejection of a demand for unconditional surrender, prompted President Truman to authorize use of the bomb.

The atomic bomb devastates Hiroshima, Japan: Hiroshima was devastated following the atomic bomb attack by Enola Gay on August 6, 1945. The bomb detonated at 8:16 a.m., 1,900 feet above Shima Hospital. The fireball was so intense, it melted granite. The concussion obliterated virtually every building within two miles. A column of smoke and debris as high as Mount Everest rose into the sky. Upwards of 80,000 people were killed outright. Thousands would die later, many from radiation sickness. Nevertheless, the bombing probably saved lives elsewhere in Japan. Had the bomb not encouraged an end to the war, millions of Japanese might have died of starvation, of disease, in fire-bombing raids, and in efforts to resist a U.S. ground invasion of the home islands.

Below is a Japanese journalist's description of Hiroshima immediately following the atomic blast, as told to Marcel Junod of the Red cross.

Beyond the zone of utter death in which nothing remained alive, houses collapsed in a whirl of beams, bricks and girders. Up to about three miles from the center of the explosion lightly built houses were flattened as though they had been built of cardboard. Those who were inside were either killed or wounded. Those who managed to extricate themselves by some miracle found themselves surrounded by a ring of fire....

About half an hour after the explosion, whilst the sky all around Hiroshima was still cloudless, a fine rain began to fall on the town and went on for about five minutes. It was caused by the sudden rise of over-heated air to a great height, where it condensed and fell back as rain. Then a violent wind rose and the fires extended with terrible rapidity, because most Japanese houses are built only of timber and straw.

By the evening the fire began to die down and then it went out. There was nothing left to burn, Hiroshima had ceased to exist.

How Japanese died in the atomic attacks: Stripped of flesh by the blast, the skeletons of Hiroshima bombing victims were found in the rubble houses. Many of those exposed to the initial fireball were simply vaporized -- some leaving only their silhouettes imprinted on walls or pavement. Others died of thermal burns, from flying debris, in the collapse of buildings, or in the resulting fires. Japanese relief efforts began within days, as rice, wheat, sandals, and other necessities arrived. Medical care was less prompt, since many physicians had been killed or injured in the bombing. Thousands of victims succumbed within weeks to a mysterious illness later identified as radiation sickness. The Japanese government downplayed the carnage and expressed a determination to fight on.

See the next page for a detailed timeline of World War II events in July and August of 1945, when atomic attacks forced Japan into surrender.

To follow more major events of World War II, see:

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