The official end of World War II is marked by the signing of the formal surrender of Japan on September 2, 1945. This event took place aboard the USS Missouri in Tokyo Bay, following Japan's earlier surrender announcement on August 15, 1945, after the United States dropped atomic bombs on Hiroshima and Nagasaki. The conclusion of the war brought about significant geopolitical changes, leading to the emergence of the United States and the Soviet Union as superpowers, the establishment of the United Nations, and the beginnings of the Cold War. The war's end also initiated efforts for decolonization and reconstruction in many affected regions worldwide.