In desperate times, the enemy of your enemy becomes your friend. During World War II, the United States, Great Britain and the Soviet Union would never have been three-way allies had they not shared a mortal enemy in Adolf Hitler. The Americans were isolationists, the Brits were imperialists and the Soviets were Communists—the unlikeliest of political bedfellows.

But once Germany made its plans for world domination painfully clear, the leaders of the “Big Three” nations—Franklin D. Roosevelt, Winston Churchill and Joseph Stalin—understood that the only way to defeat Nazism was to put their significant political and personal differences aside in the name of global security. The only question was, how much was each leader willing to sacrifice to make the uneasy alliance work?

Roosevelt, the progressive pragmatist

As WWII broke out in 1939, FDR was on the verge of being elected to a historic third term as a popular and progressive president. The U.S. Congress and the American people were hoping to sit WWII out. America felt it had already sacrificed more than enough young lives in WWI and didn’t want to be pulled into another blood-soaked European conflict.

After Germany invaded Poland in September 1939, in direct defiance of British and French demands, FDR refused to enter the fray, instead declaring the U.S. neutral. Even when the Nazis steamrolled into Belgium, Holland and Luxembourg the following spring, prompting Churchill to call for strong American support, FDR and Congress refused to do anything more than provide financial assistance and some military equipment for the Allied cause.

The relationship between FDR and Churchill echoed the strained alliance between the two greatest Western democracies. Socially, the two men were a perfect match—both gregarious and aristocratic, with a flair for conversation. But Churchill, a decorated soldier and officer, was a passionate defender of the British Empire, which still controlled vast territories from Africa to India to the Far East. FDR, on the other hand, was a harsh critic of what he saw as the evils of imperialism.

There was no such easy social rapport between FDR and Stalin, a Communist dictator who actively purged all political opposition, even if it meant killing or imprisoning people in the highest ranks of the Soviet government and military. Yet Roosevelt recognized early the political benefits of a positive relationship between the U.S, and the USSR, particularly as a buffer against the Japanese. In fact, in his first year as president, FDR took action to recognize the existence of the Soviet Union and normalize diplomatic relationships with the Kremlin.

Through 1940 and most of 1941, the U.S. remained neutral even as German bombers pummeled British cities in nightly “blitz” attacks against both military and civilian targets. During that same period, Hitler reneged on his non-aggression pact with Stalin and invaded the USSR on June 22, 1941, rekindling war between the Nazi and Communist nations. FDR’s primary response in both cases was to extend lend-lease agreements to Churchill and Stalin for U.S.-built weapons and supplies.

Then, on December 7, 1941, the Japanese attacked Pearl Harbor, forcing the U.S. to declare war on Japan. Germany and Italy, the two other Axis powers, declared war on America on December 11. The U.S. had entered WWII, like it or not.

The Grand Alliance: a three-way shotgun marriage

On January 1, 1942, less than a month after Pearl Harbor, the U.S,, Great Britain and the USSR signed the “Declaration by United Nations,” a legally non-binding document that nevertheless yoked the Big Three in a grand alliance for their mutual survival. None of the three great powers could defeat Hitler on their own, but together they plotted to divide and weaken the seemingly unstoppable German forces.

Churchill deeply distrusted Stalin, and Stalin, famously paranoid, didn’t trust anyone. From the start, FDR found himself in the middle, assuaging Churchill’s fears of a Communist takeover of Europe while feeding Stalin’s aspirations for the Soviet Union’s entry into the upper echelons of political and economic power.

In a private message to Churchill at the beginning of the tense three-way marriage, FDR recognized the British prime minister’s apprehensions, while making a case for bringing the Soviet Union into the circle of “civilized nations.”

“We are all in to the necessity of having the USSR as a fully accepted and equal member of an association of the great powers formed for the purpose of preventing international war,” FDR wrote to Churchill in 1944, “It should be possible to accomplish this by adjusting our differences through compromise by all the parties concerned and this ought to tide things over for a few years until the child learns to toddle.”

How FDR won over ‘Uncle Joe’ at the Tehran Conference

FDR, Churchill and Stalin met together for the first time in November of 1943 during the historic Tehran Conference. From the moment the Americans entered the war, Stalin had been pushing for a joint British-American invasion of Western Europe to draw German soldiers from the Eastern front, where the Soviets were sustaining massive losses. In Tehran, the Americans and Brits committed to a massive 1944 invasion of coastal France (“Operation Overlord”) in return for Stalin’s promise to join the fight against Japan.

In Tehran, Roosevelt also met privately with Stalin to discuss the Soviet Union’s central role in a post-war United Nations. Roosevelt shared his vision with Stalin of a peaceful world governed by the “four policemen” of the United States—Britain, China and the Soviet Union—and showed “Uncle Joe” that America was willing to negotiate directly with the USSR to serve their mutual interests.

“What Stalin wanted to do was to revive Russia as a great world power,” says Susan Butler, author of Roosevelt and Stalin: Portrait of a Partnership. “Stalin was perfectly happy to do what FDR wanted. Roosevelt was extending his hand—if you behave, you can be my equal.”

“In my personal view, I think that Roosevelt was the only person that Stalin did trust,” adds Butler. “I think that they had an understanding of the world. It has nothing to do with the fact that Stalin was a paranoid nut. If Stalin trusted anyone, he trusted Roosevelt, because Stalin fared very well at the hands of FDR.”

The Big Three, Joseph Stalin, Franklin D. Roosevelt, Winston Churchill
Corbis/Getty Images
Russian Premier Joseph Stalin, President Franklin Roosevelt, and British Prime Minister Winston Churchill meeting in Tehran, Iran in late 1943.

At Yalta, an alliance on the brink

The second and final time the three great leaders met was at the Yalta Conference in February of 1945. This meeting was very different from Tehran, with FDR visibly ill and an Allied victory over Germany in plain sight.

“At that point, FDR, Churchill and Stalin were more concerned about stopping World War Three,” says Butler. “They thought there was a great possibility that Germany was going to try once more to rule the world. [The post-war formation of] the United Nations was the primary concern of FDR, which is why he called for the conference at Yalta.”

At Yalta, the three men assumed that the War with Japan would rage on long after Hitler surrendered. In order to secure continued Soviet military support against the Japanese, and win Stalin’s full cooperation in the United Nations, FDR and Churchill agreed to a number of concessions with historic consequences. After the war, the Soviets would retain control over part of Germany and the USSR would also have free reign to influence the governments of its Eastern European and Asian neighbors.

There were bright hopes that the cooperative spirit of the Grand Alliance would persist after WWII, but with FDR’s death only two months after Yalta, the political dynamics changed dramatically. The U.S., now under the command of hardliner Harry Truman, reneged on FDR’s promise to loan money to the Soviets for rebuilding their damaged economy. Coupled with America and Britain’s fears over the spread of communism in Eastern Europe and Asia, the stage was set for the Cold War.

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