It is now pretty well agreed that the Big Three summit conference at Yalta—the United States, the United Kingdom, and the Soviet Union—from February 4 to February 11, 1945, was where, when, and how the Cold War began. The site of the Yalta conference was the former palace of Tsar Nicholas II on the southern Crimean shore of the Black Sea. Earlier summit conferences had been held in Cairo and Tehran. However, Yalta, coming as it did toward the end of the war in the European theater, was the crucial one.
Stalin was in full possession of Poland, as once had been Catherine the Great, and nothing short of war would budge him out of Poland. Neither President Roosevelt nor Prime Minister Churchill was ready or willing to demand a free and democratic Poland.
Yalta proved once more that what you haven’t won on the field of battle you cannot win at the conference table (at least when you were dealing with Stalin). This was the military situation as Yalta opened: General Eisenhower had under his command four million men in 85 divisions, and they were nowhere near Berlin. The Red Army, embanked on the Oder River and awaiting Stalin’s order to begin the final assault on Berlin, had three times as many men and divisions: 12 million soldiers in 300 divisions.
Stalin signed an agreement at Yalta, along with FDR and Churchill, that contained this crucial paragraph flouted before the ink was dry by the Soviet dictator:
The establishment of order in Europe and the rebuilding of national economic life must be achieved by processes, which will enable the liberated peoples to destroy the last vestiges of nazism and fascism and to create democratic institutions of their own choice. This is a principle of the Atlantic Charter—the right of all people to choose the form of government under which they will live.
After seizing Poland, Stalin then took over most of Central and Eastern Europe with little difficulty. Stalin broke his agreement and there was nobody to say him nay. FDR was already a dying man at Yalta (blood pressure: 260/150 mmHg). He presented his report on Yalta to Congress on March 1 sitting down. On April 12, he was dead of a massive cerebral hemorrhage. Yes there was a conspiracy in the White House to conceal the disabling illnesses of the four-term president. (For a fully documented report about FDR’s health, I recommend The Dying President: Franklin D. Roosevelt 1944–1945 by Robert Ferrell.)