BACKGROUND
By the end of July 1945, the Imperial Japanese Navy was incapable of conducting operations and an Allied invasion of Japan was imminent. While publicly stating their intent to fight on to the bitter end, Japan's leaders at the Supreme Council for the Direction of the War (the "Big Six") were privately making entreaties to the neutral Soviet Union to mediate peace on terms favorable to the Japanese. The Soviets, meanwhile, were preparing to attack the Japanese, in fulfillment of their promises to the United States and the United Kingdom made at the Tehran and Yalta Conferences.
THE POTSDAM DECLARATION
The leaders of the major Allied powers met at the Potsdam Conference from July 16 to August 2, 1945 . The participants were the Soviet Union, the United Kingdom, and the United States, represented by Josef Stalin, Winston Churchill (who was later replaced by Clement Attlee when the Labor Party won the British elections), and Harry S. Truman, respectively.
The Potsdam Conference was held at Cecilienhof, the home of Crown Prince Wilhelm Hohenzollern, in Potsdam, occupied Germany, from July 17 to August 2, 1945. Participants were the Soviet Union, the United Kingdom and the United States.
The three powers were represented by Communist Party General Secretary Joseph Stalin, Prime Ministers Winston Churchill and, later, Clement Attlee, and President Harry S. Truman. In the photo: Stalin, Truman, and Attlee at Potsdam.
In addition to the Potsdam Agreement, which focused on the post-war order in Europe, on 26 July, Churchill, Truman, and Chiang Kai-shek, Chairman of the Nationalist Government of China (the Soviet Union was not at war with Japan) issued the Potsdam Declaration which outlined the terms of surrender for Japan during World War II in Asia.
Japan was given an ultimatum to surrender (in the name of the United States, Great Britain and China) or meet "prompt and utter destruction" but the atomic bomb was not mentioned. The terms of the declaration specified the matters of Japanese authorities (e.g., the elimination of proponents of the empire), territory (including occupation by the Allies), demilitarization, treatment of individuals defined as war criminals, post-war democracy, and economy. Contrary to what had been intended at its conception, the declaration made no direct mention of the Emperor. Allied intentions on issues of utmost importance to the Japanese, including whether Hirohito was to be regarded as one of those who had "misled the people of Japan" or even a war criminal, or alternatively whether the Emperor might potentially become part of a "peacefully inclined and responsible government" were left unstated.
The "prompt and utter destruction" clause has been interpreted as a veiled warning about American possession of the atomic bomb which had been successfully tested in New Mexico on July 16, 1945, the day before the Potsdam Conference opened. Prime minister Kantarō Suzuki did not respond.
OCCUPATION AND SURRENDER
On August 6, 1945, the United States dropped an atomic bomb on the city of Hiroshima. Late in the evening of August 8, 1945, in accordance with Yalta agreements but in violation of the Soviet–Japanese Neutrality Pact, the Soviet Union declared war on Japan, and soon after midnight on August 9, 1945, it invaded the Japanese puppet state of Manchukuo. Later that day the United States dropped an atomic bomb on Nagasaki. The combined shock of these events caused Emperor Hirohito to intervene and order the Big Six to accept the terms for ending the war that the Allies had set down in the Potsdam Declaration. After several more days of behind-the-scenes negotiations and a failed coup d'état, Hirohito gave a recorded radio address to the nation on August 15. In the radio address, he announced the surrender of Japan.
On August 28, 1945, the occupation of Japan by the Supreme Commander of the Allied Powers began. Supreme Commander of the Allied Powers Douglass MacArthur arrived in Tokyo on August 30, and immediately decreed several laws: no Allied personnel were to assault Japanese people; no Allied personnel were to eat the scarce Japanese food; flying the Hinomaru or "Rising Sun" flag was severely restricted. The formal surrender occurred on September 2, 1945, when representatives from the Empire of Japan signed the Japanese Instrument of Surrender in Tokyo Bay aboard the USS Missouri. Japanese Foreign Minister Shigemitsu signed for the Japanese government, while Gen. Umezu signed for the Japanese armed forces.
After the formal surrender, investigations into Japanese war crimes began. At a meeting with MacArthur later in September, Emperor Hirohito offered to take blame for the war crimes, but his offer was rejected, and he was never tried. Legal procedures for the International Military Tribunal for the Far East were issued on January 19, 1946.
Following the signing of the instrument of surrender, many further surrender ceremonies took place across Japan's remaining holdings in the Pacific. Japanese forces in South East Asia surrendered on September 12, 1945 in Singapore. Taiwan's Retrocession Day (October 25), marked the end of Japanese rule of Taiwan and the subsequent rule by the Republic Of China government. It was not until 1947 that all prisoners held by America and Britain were repatriated. As late as April 1949, China still held more than 60,000 Japanese prisoners.
The logistical demands of the surrender were formidable. After Japan's capitulation, more than 5,400,000 Japanese soldiers and 1,800,000 Japanese sailors were taken prisoner by the Allies. The damage done to Japan's infrastructure, combined with a severe famine in 1946, further complicated the Allied efforts to feed the Japanese POWs and civilians.
The state of war between the United States and Japan officially ended when the Treaty of San Francisco took effect on April 28, 1952. Japan and the Soviet Union formally made peace four years later, when they signed the Soviet–Japanese Joint Declaration of 1956.
Surrender of Japan, Tokyo Bay, 2 September 1945
General of the Army Douglas MacArthur, Supreme Allied Commander, reading his speech to open the surrender ceremonies, on board USS Missouri (BB-63)