Given such abysmal precedents, it is not surprising that British Prime Minister Winston Churchill and U.S. President Franklin D. Roosevelt placed great emphasis on maintaining a smooth working relationship among the Allied powers during World War II. This complex relationship was hammered out in a series of conferences held throughout the war, several involving direct dialogues among the various heads of government. For Churchill and Roosevelt, who prided themselves on their ability to finesse negotiations through charisma, such meetings provided a perfect medium for deal making.
The conference system produced a remarkable degree of harmony between the British and Americans. While relations with Soviet leader Josef Stalin, the third principal in the Allied triumvirate, were never so straightforward, it was at least possible to keep the Soviet Union committed to the fight against the Axis powers. The conferences also established workable, if far from ideal, settlements of postwar issues.
When Churchill and Roosevelt first met at Placentia Bay, Newfoundland, in August 1941, there were technically no Allied powers because there was no alliance of which to speak. The United States was still (nominally) neutral, and while the Soviet Union was engaged in a bitter fight with German forces, it was doing so neither with support from nor in coordination with the West. The Newfoundland conference was therefore more symbolic than substantive, although it did produce a powerful statement of democratic principles in the form of the Atlantic Charter. Perhaps more significantly, it led the way for the so-called Three-Power Conference in Moscow (29 September–1 October 1941), at which Churchill and Roosevelt's representatives, Lord Beaverbrook and W. Averell Harriman, agreed to extend American Lend-Lease support to the Soviets.
After the United States entered the war in December 1941, these tentative contacts were supplanted by full-fledged diplomatic commitments. Churchill traveled to Washington in the immediate wake of the Pearl Harbor attack, and at the resulting Anglo-American conference (code name arcadia) during 22 December 1941–14 January 1942, the two nations negotiated the mechanisms through which they would fight the remainder of World War II together, including the Combined Chiefs of Staff Committee and joint boards to coordinate shipping, raw material usage, and industrial production. In May 1942 the two Western powers drew the Soviets closer to the new alliance system—known since January as the United Nations (UN)—via an Anglo-Soviet Treaty (26 May 1942) and a meeting between Roosevelt and Soviet Foreign Minister Vyacheslav Molotov on 29 May 1942. These somewhat tentative steps helped reduce mutual suspicions between the liberal-capitalist and communist powers.
It should be noted, however, that the American-British relationship was not without tension. At the Second Washington Conference in June 1942, it became clear that American and British leaders had very different ideas about the conduct of the war. Although the Germany First strategy went largely unquestioned, the Americans' eagerness to launch a full-scale invasion of the European mainland as soon as possible clashed with the more cautious British proposal to restrict activities to the periphery until the Axis had been sufficiently worn down. At this stage in the war, the British view tended to predominate, as much for practical reasons as for the cogency of its appeal: the two allies simply lacked the means to launch anything more than secondary operations. It remained vital to keep the Soviets in the fight, however, hence Churchill's August 1943 visit to Moscow, an uncomfortable meeting in which the British leader had to inform Stalin that a second European front remained, for the time being, an impossibility.
The successful Allied invasion of French North Africa in November 1942 was followed by the Casablanca Conference (14–24 January 1943) at which a more confident Roosevelt declared for the first time the Allied policy of unconditional surrender. He and Churchill also approved the round-the-clock strategic bombing campaign against Germany. At a follow-up conference four months later in Washington, D.C. (11–25 May 1943), the Americans agreed to delay a cross-channel attack for another year, but they extracted from the still-skeptical British a deadline for such action of 1 May 1944. The details of this future offensive were elaborated at the first conference between the Western Allies in Quebec in August 1943, at which the top secret plans for the Manhattan Project—the atomic bomb program—were also thrashed out. By mid-1943, with the German assault on the Eastern Front finally blunted at Kursk and with Italy on the verge of collapse after the invasion of Sicily, the main issue for the alliance was not so much the defeat of the Axis but rather how and when that defeat would come.
There remained, nonetheless, great concern about the West's relationship with the Soviet Union. Might Stalin negotiate a separate peace with Germany? And what of the future map of Europe after an Allied victory? Such concerns were central to the four-power Moscow Conference (19 October–1 November 1943), at which representatives of the Big Three powers and Nationalist-controlled China ratified the unconditional surrender doctrine and agreed to the establishment of a postwar organization for global security. To solidify the still-shaky Allied relationship, Churchill and Roosevelt also suggested a personal meeting with Stalin. At the preparatory Anglo-American talks in Cairo in November 1943, Churchill believed that he had persuaded his American colleague to take a less emphatic line on the timing of the Normandy landings. To his considerable dismay, however, Roosevelt ignored his concession in face-to-face discussions with Stalin at the Tehran Conference (28 November–1 December 1943), where he enthusiastically embraced the cross-channel invasion, Operation overlord. Tehran marked the fulcrum point at which American diplomatic efforts shifted decisively toward a bilateral relationship with the Soviet Union, thereby marginalizing its weaker British ally.
By 1944, conference proceedings were dominated by the shaping of the postwar world. At Bretton Woods (1 July–15 July 1944) and Dumbarton Oaks (21–29 August 1944), the Allies drafted constitutions for the International Monetary Fund (IMF) and the UN, centerpieces of the new postwar financial and political order. Such bold declarations of idealistic principle contrasted with the rather murkier realpolitik conducted at the same time behind closed doors. At the Second Quebec Conference in September 1944, Churchill attempted, without much success, to shift the focus of the Pacific war toward the reconstitution of the British Empire in Southeast Asia. While in Moscow the following month, he made the notorious percentages agreement with Stalin that divided Eastern Europe and the Balkans into western and eastern spheres of influence. This spirit of cynicism or, from another point of view, sober realism pervaded the last meeting among Roosevelt, Stalin, and Churchill at Yalta (4 February–11 February 1945), at which the de facto division of Europe was confirmed and a number of Russo-American agreements on the future shape of East Asia were drawn up without regard for the British or Chinese.
The Allied conference era was rapidly concluding. The war against Germany was in its closing days when the delegates of the new UN met in San Francisco in April 1945 for their inaugural session. A month later President Harry S. Truman traveled to the ruins of Hitler's defeated Reich to meet Churchill, his soon-to-be replacement Clement Attlee, and Stalin at Potsdam from 17 July–2 August 1945. At Potsdam, the three partners delivered to Japan a final ultimatum for surrender and attempted to settle the disputed future of Poland, but despite the glow of certain victory, it was evident that an alliance born of expedience could not survive in the postwar environment. Potsdam marked the effective end of wartime comradeship between East and West and the beginning of forty years of Cold War.
Gardner, Lloyd C. Spheres of Influence: The Great Powers Partition Europe, from Munich to Yalta. Chicago: Ivan R. Dee, 1993.; Smith, Gaddis. American Diplomacy during the Second World War, 1941–1945. New York: Knopf, 1985.; Woods, Randall B. A Changing of the Guard: Anglo-American Relations, 1941–1946. Chapel Hill: University of North Carolina Press, 1990.