The Potsdam Conference concerned meetings held by the principal Allies in World War II (the United States, the USSR, and Great Britain). They came together from July 17 to August 2, 1945 to clarify and implement agreements previously reached at the Yalta Conference. The chief representatives were President Truman, Premier Stalin, Prime Minister Churchill, and after Churchill's defeat in the British elections, Prime Minister Attlee.

As a result of the conference, the so-called Potsdam Agreement transferred the chief authority in Germany to the American, Russian, British, and French military commanders in their respective zones of occupation and to a four-power Allied Control Council for matters regarding the whole of Germany. The Allies set up a new system of rule for Germany, aimed at outlawing National Socialism and abolishing Nazi ideology, at disarming Germany and never allowing it to again become a military power, and at fostering democratic ideals and introducing representative and elective principles of government. Also, the Potsdam Conference presented an ultimatum to Japan. It offered Japan the choice between unconditional surrender or total destruction.

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