What happened at the "Big Three" conferences between the Allies during World War II

The first involvement of the United States in the wartime conferences between the Allied nations opposing the Axis powers actually occurred before the nation formally entered World War II. In August 1941, President Franklin Roosevelt and British Prime Minister Winston Churchill met secretly and devised an eight-point statement of war aims known as the Atlantic Charter, which included a pledge that the Allies would not accept territorial changes resulting from the war in Europe. Following the Japanese attack on Pearl Harbor, the wartime conferences focused on establishing a second front. At Casablanca in January 1943, Roosevelt and Churchill agreed to fight until the Axis powers surrendered unconditionally. In a November 1943 meeting in Egypt with Chinese leader Chiang Kai-shek, Roosevelt and Churchill agreed to a pre-eminent role for China in postwar Asia. The next major wartime conference included Roosevelt, Churchill, and the leader of the Soviet Union, Joseph Stalin. Meeting at Tehran following the Cairo Conference, the “Big Three” secured confirmation on the launching of the cross-channel invasion and a promise from Stalin that the Soviet Union would eventually enter the war against Japan. In 1944, conferences at Bretton Woods and Dumbarton Oaks created the framework for international cooperation in the postwar world. In February 1945, the “Big Three” met at the former Russian czar’s summer palace in the Crimea. Yalta was the most important and by far the most controversial of the wartime meetings. Recognizing the strong position that the Soviet Army possessed on the ground, Churchill and an ailing Roosevelt agreed to a number of compromises with Stalin that allowed Soviet hegemony to remain in Poland and other Eastern European countries, granted territorial concessions to the Soviet Union, and outlined punitive measures against Germany, including an occupation and reparations in principle. Stalin did guarantee that the Soviet Union would declare war on Japan within six months. The last meeting of the “Big Three” occurred at Potsdam in July 1945, where the tension that would erupt into the cold war was evident. Despite the end of the war in Europe and the revelation of the existence of the atomic bomb to the Allies, neither President Harry Truman, Roosevelt’s successor, nor Clement Atlee, who mid-way through the conference replaced Churchill, could come to agreement with Stalin on any but the most minor issues. The most significant agreement was the issuance of the Potsdam Declaration to Japan demanding an immediate and unconditional surrenderand threatening Japan with destruction if they did not comply. With the Axis forces defeated, the wartime alliance soon devolved into suspicion and bitterness on both sides. https://history.state.gov/milestones/1937-1945/war-time-conferences

The Casablanca Conference, 1943 The Casablanca Conference was a meeting between U.S. President Franklin D. Roosevelt and British Prime Minister Winston Churchill in the city of Casablanca, Morocco that took place from January 14–24, 1943. While Soviet Premier Joseph Stalin received an invitation, he was unable to attend because the Red Army was engaged in a major offensive against the German Army at the time. The most notable developments at the Conference were the finalization of Allied strategic plans against the Axis powers in 1943, and the promulgation of the policy of “unconditional surrender.” The Casablanca Conference took place just two months after the Anglo-American landings in French North Africa in November 1942. At this meeting, Roosevelt and Churchill focused on coordinating Allied military strategy against the Axis powers over the course of the coming year. They resolved to concentrate their efforts against Germany in the hopes of drawing German forces away from the Eastern Front, and to increase shipments of supplies to the Soviet Union. While they would begin concentrating forces in England in preparation for an eventual landing in northern France, they decided that first they would concentrate their efforts in the Mediterranean by launching an invasion of Sicily and the Italian mainland designed to knock Italy out of the war. They also agreed to strengthen their strategic bombing campaign against Germany. Finally, the leaders agreed on a military effort to eject Japan from Papua New Guinea and to open up new supply lines to China through Japanese-occupied Burma. On the final day of the Conference, President Roosevelt announced that he and Churchill had decided that the only way to ensure postwar peace was to adopt a policy of unconditional surrender. The President clearly stated, however, that the policy of unconditional surrender did not entail the destruction of the populations of the Axis powers but rather, “the destruction of the philosophies in those countries which are based on conquest and the subjugation of other people.” The policy of demanding unconditional surrender was an outgrowth of Allied war aims, most notably the Atlantic Charter of August 1941, which called for an end to wars of aggression and the promotion of disarmament and collective security. Roosevelt wanted to avoid the situation that had followed the First World War, when large segments of German society supported the position, so deftly exploited by the Nazi party, that Germany had not been defeated militarily, but rather, had been “stabbed in the back” by liberals, pacifists, socialists, communists, and Jews. Roosevelt also wished to make it clear that neither the United States nor Great Britain would seek a separate peace with the Axis powers. https://history.state.gov/milestones/1937-1945/casablanca

The Tehran Conference, 1943 The Tehran Conference was a meeting between U.S. President Franklin Delano Roosevelt, British Prime Minister Winston Churchill, and Soviet Premier Joseph Stalin in Tehran, Iran, between November 28 and December 1, 1943. During the Conference, the three leaders coordinated their military strategy against Germany and Japan and made a number of important decisions concerning the post World War II era. The most notable achievements of the Conference focused on the next phases of the war against the Axis powers in Europe and Asia. Roosevelt, Churchill, and Stalin engaged in discussions concerning the terms under which the British and Americans finally committed to launching Operation Overlord, an invasion of northern France, to be executed by May of 1944. The Soviets, who had long been pushing the Allies to open a second front, agreed to launch another major offensive on the Eastern Front that would divert German troops away from the Allied campaign in northern France. Stalin also agreed in principle that the Soviet Union would declare war against Japan following an Allied victory over Germany. In exchange for a Soviet declaration of war against Japan, Roosevelt conceded to Stalin’s demands for the Kurile Islands and the southern half of Sakhalin, and access to the ice-free ports of Dairen (Dalian) and Port Arthur (Lüshun Port) located on the Liaodong Peninsula in northern China. The exact details concerning this deal were not finalized, however, until the Yalta Conference of 1945. At Tehran, the three Allied leaders also discussed important issues concerning the fate of Eastern Europe and Germany in the postwar period. Stalin pressed for a revision of Poland’s eastern border with the Soviet Union to match the line set by British Foreign Secretary Lord Curzon in 1920. In order to compensate Poland for the resulting loss of territory, the three leaders agreed to move the German-Polish border to the Oder and Neisse rivers. This decision was not formally ratified, however, until the Potsdam Conference of 1945. During these negotiations Roosevelt also secured from Stalin his assurance that the Republics of Lithuania, Latvia, and Estonia would be reincorporated into the Soviet Union only after the citizens of each republic voted on the question in a referendum. Stalin stressed, however, that the matter would have to be resolved “in accordance with the Soviet constitution,” and that he would not consent to any international control over the elections. Roosevelt, Churchill, and Stalin also broached the question of the possible postwar partition of Germany into Allied zones of occupation and agreed to have the European Advisory Commission “carefully study the question of dismemberment” before any final decision was taken. Broader international cooperation also became a central theme of the negotiations at Tehran. Roosevelt and Stalin privately discussed the composition of the United Nations. During the Moscow Conference of the Foreign Ministers in October and November of 1943, the United States, Britain, China, and the Soviet Union had signed a four-power declaration whose fourth point called for the creation of a “general international organization” designed to promote “international peace and security.” At Tehran, Roosevelt outlined for Stalin his vision of the proposed organization in which the future United Nations would be dominated by “four policemen” (the United States, Britain, China, and Soviet Union) who “would have the power to deal immediately with any threat to the peace and any sudden emergency which requires action.” Finally, the three leaders issued a “Declaration of the Three Powers Regarding Iran.” Within it, they thanked the Iranian Government for its assistance in the war against Germany and promised to provide it with economic assistance both during and after the war. Most importantly, the U.S., British, and Soviet Governments stated that they all shared a “desire for the maintenance of the independence, sovereignty, and territorial integrity of Iran.” Roosevelt secured many of his objectives during the Conference. The Soviet Union had committed to joining the war against Japan and expressed support for Roosevelt’s plans for the United Nations. Most importantly, Roosevelt believed that he had won Stalin’s confidence by proving that the United States was willing to negotiate directly with the Soviet Union and, most importantly, by guaranteeing the opening of the second front in France by the spring of 1944. However, Stalin also gained tentative concessions on Eastern Europe that would be confirmed during the later wartime conferences. https://history.state.gov/milestones/1937-1945/tehran-conf

The Yalta Conference, 1945 The Yalta Conference took place in a Russian resort town in the Crimea from February 4–11, 1945, during World War Two. At Yalta, U.S. President Franklin D. Roosevelt, British Prime MinisterWinston Churchill, and Soviet Premier Joseph Stalin made important decisions regarding the future progress of the war and the postwar world.

The Allied leaders came to Yalta knowing that an Allied victory in Europe was practically inevitable but less convinced that the Pacific war was nearing an end. Recognizing that a victory over Japan might require a protracted fight, the United States and Great Britain saw a major strategic advantage to Soviet participation in the Pacific theater. At Yalta, Roosevelt and Churchill discussed with Stalin the conditions under which the Soviet Union would enter the war against Japan and all three agreed that, in exchange for potentially crucial Soviet participation in the Pacific theater, the Soviets would be granted a sphere of influence in Manchuria following Japan’s surrender. This included the southern portion of Sakhalin, a lease at Port Arthur (now Lüshunkou), a share in the operation of the Manchurian railroads, and the Kurile Islands. This agreement was the major concrete accomplishment of the Yalta Conference. The Allied leaders also discussed the future of Germany, Eastern Europe and the United Nations. Roosevelt, Churchill, and Stalin agreed not only to include France in the postwar governing of Germany, but also that Germany should assume some, but not all, responsibility for reparations following the war. The Americans and the British generally agreed that future governments of the Eastern European nations bordering the Soviet Union should be “friendly” to the Soviet regime while the Soviets pledged to allow free elections in all territories liberated from Nazi Germany. Negotiators also released a declaration on Poland, providing for the inclusion of Communists in the postwar national government. In discussions regarding the future of the United Nations, all parties agreed to an American plan concerning voting procedures in the Security Council, which had been expanded to five permanent members following the inclusion of France. Each of these permanent members was to hold a veto on decisions before the Security Council. Initial reaction to the Yalta agreements was celebratory. Roosevelt and many other Americans viewed it as proof that the spirit of U.S.-Soviet wartime cooperation would carry over into the postwar period. This sentiment, however, was short lived. With the death of Franklin D. Roosevelt on April 12, 1945, Harry S. Truman became the thirty-third president of the United States. By the end of April, the new administration clashed with the Soviets over their influence in Eastern Europe, and over the United Nations. Alarmed at the perceived lack of cooperation on the part of the Soviets, many Americans began to criticize Roosevelt’s handling of the Yalta negotiations. To this day, many of Roosevelt’s most vehement detractors accuse him of “handing over” Eastern Europe and Northeast Asia to the Soviet Union at Yalta despite the fact that the Soviets did make many substantial concessions. https://history.state.gov/milestones/1937-1945/yalta-conf