<P> On August 6, 1945, at 8: 15 AM local time, the United States detonated an atomic bomb over the Japanese city of Hiroshima . Sixteen hours later, American President Harry S. Truman called again for Japan's surrender, warning them to "expect a rain of ruin from the air, the like of which has never been seen on this earth ." Late in the evening of August 8, 1945, in accordance with the 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, the Soviet Union invaded the Imperial Japanese puppet state of Manchukuo . Later in the day, the United States dropped a second atomic bomb, this time on the Japanese city of Nagasaki . Following these events, Emperor Hirohito intervened and ordered the Supreme Council for the Direction of the War to accept the terms the Allies had set down in the Potsdam Declaration for ending the war . After several more days of behind - the - scenes negotiations and a failed coup d'état, Emperor Hirohito gave a recorded radio address across the Empire on August 15 . In the radio address, called the Jewel Voice Broadcast (玉音 放送, Gyokuon - hōsō), he announced the surrender of Japan to the Allies . </P> <P> On August 28, the occupation of Japan led by the Supreme Commander for the Allied Powers began . The surrender ceremony was held on September 2, aboard the United States Navy battleship USS Missouri, at which officials from the Japanese government signed the Japanese Instrument of Surrender, thereby ending the hostilities . Allied civilians and military personnel alike celebrated V-J Day, the end of the war; however, isolated soldiers and personnel from Japan's far - flung forces throughout Asia and the Pacific refused to surrender for months and years afterwards, some even refusing into the 1970s . The role of the atomic bombings in Japan's unconditional surrender, and the ethics of the two attacks, is still debated . The state of war formally ended when the Treaty of San Francisco came into force on April 28, 1952 . Four more years passed before Japan and the Soviet Union signed the Soviet--Japanese Joint Declaration of 1956, which formally brought an end to their state of war . </P> <P> By 1945, the Japanese had suffered a string of defeats for nearly two years in the South West Pacific, the Marianas campaign, and the Philippines campaign . In July 1944, following the loss of Saipan, General Hideki Tōjō was replaced as prime minister by General Kuniaki Koiso, who declared that the Philippines would be the site of the decisive battle . After the Japanese loss of the Philippines, Koiso in turn was replaced by Admiral Kantarō Suzuki . The Allies captured the nearby islands of Iwo Jima and Okinawa in the first half of 1945 . Okinawa was to be a staging area for Operation Downfall, the Allied invasion of the Japanese Home Islands . Following Germany's defeat, the Soviet Union began quietly redeploying its battle - hardened European forces to the Far East, in addition to about forty divisions that had been stationed there since 1941, as a counterbalance to the million - strong Kwantung Army . </P> <P> The Allied submarine campaign and the mining of Japanese coastal waters had largely destroyed the Japanese merchant fleet . With few natural resources, Japan was dependent on raw materials, particularly oil, imported from Manchuria and other parts of the East Asian mainland, and from the conquered territory in the Dutch East Indies . The destruction of the Japanese merchant fleet, combined with the strategic bombing of Japanese industry, had wrecked Japan's war economy . Production of coal, iron, steel, rubber, and other vital supplies was only a fraction of that before the war . </P>

Who surrendered first in ww2 japan or germany