Even before the war in Europe ended, the Allied leaders met to plan the postwar world. They wanted to avoid the mistakes of 1919, when the U.S. stayed out of the League of Nations.
Key idea
At Yalta (February 1945) and Potsdam (July 1945) the Allies planned postwar Europe. The United Nations was founded in 1945, with the U.S. as a permanent member of the Security Council.
| Meeting | When | Leaders | Main decisions |
|---|---|---|---|
| Yalta (Crimea) | February 4–11, 1945 | Roosevelt, Churchill, Stalin | Germany divided into occupation zones; Stalin promised free elections in Poland and to fight Japan within three months of Germany's defeat; plans for the UN |
| San Francisco Conference | April to June 1945 | 50 nations | The UN Charter signed June 26, 1945; in force October 24, 1945 |
| Potsdam (Germany) | July 17 to August 2, 1945 | Truman, Stalin, Churchill (then Clement Attlee) | How to occupy and disarm Germany; war crimes trials; the call for Japan's unconditional surrender |
Why it works
Why did the U.S. join the UN when it had refused the League? The war had shown that oceans no longer kept America safe, and leaders of both parties now favored joining; the Senate approved the Charter 89 to 2. The UN's Security Council gave five permanent members (the U.S., the Soviet Union, Britain, France and China) a veto, so the great powers would not be outvoted. The Bretton Woods conference (1944) created the International Monetary Fund and the World Bank, and the Nuremberg trials (1945 to 1946) tried Nazi leaders for war crimes.
Yalta later became controversial. Critics said Roosevelt gave Eastern Europe to Stalin; defenders answered that Soviet armies already held it and that Stalin's promise of free elections was the most the West could get. Either way, the promise was broken, and disputes over Poland and Germany opened the Cold War.
Work it through
Worked example: League versus UN
Give two differences between the League of Nations (1920) and the United Nations (1945).
- Membership: the U.S. never joined the League; it helped found the UN and joined in 1945.
- Power: the UN Security Council gives five permanent members a veto, keeping the great powers inside it.
- Both aimed to keep peace through collective security.
Answer: The U.S. joined the UN, and the great powers hold vetoes.
Common mistake
Many students think the United Nations was the League of Nations renamed. They were separate organizations. The U.S. never joined the League; it helped found the UN and joined it in 1945. The League formally dissolved in 1946.