Until then, the Japanese had been hoping that the Russians - who had previously signed a nonaggression pact with Japan - might be intermediaries in negotiating an end to the war. 8 was probably an even greater shock to Tokyo than the atomic bombing of Hiroshima two days earlier. The latest and best scholarship on the surrender, based on Japanese records, concludes that the Soviet Union’s unexpected entry into the war against Japan on Aug. But minutes of the meetings of the Japanese government reveal a more complex story. history textbooks, the default understanding of how and why the war ended. 15, 1945, has been, for many Americans and virtually all U.S. The notion that the atomic bombs caused the Japanese surrender on Aug. The 70th anniversary of the event presents an opportunity to set the record straight on five widely held myths about the bomb. Decades later, controversy and misinformation still surround the decision to use nuclear weapons during World War II. 6, 1945, the United States dropped an atomic bomb on the Japanese city of Hiroshima.