Yalta Conference
The February 1945 Big Three summit that shaped the postwar world and became shorthand for great powers dividing the map into spheres of influence.

For one week in February 1945, three men in a Crimean palace divided the future. Franklin Roosevelt, Winston Churchill, and Joseph Stalin, the 'Big Three,' met at Yalta from February 4 to 11 while Nazi Germany was visibly collapsing and the Red Army stood less than fifty miles from Berlin. Their job was to decide what the world would look like once Hitler was dead. The bargains they struck, and the one promise Stalin never kept, drew the fault line of the Cold War and gave the world a lasting shorthand: 'Yalta' became the name for great powers carving up the map over the heads of everyone living on it.
The bargains
Three big deals came out of Yalta. Germany would be occupied and divided into zones, four once Churchill won France a seat at the table, a decision that produced two German states and a divided Berlin for the next forty-five years. Stalin agreed to enter the war against Japan within about three months of Germany's surrender, in exchange for territory in the Far East: the southern half of Sakhalin, the Kurile Islands, and privileges in Manchuria. And the Soviets agreed to join the new United Nations, settling the great-power voting formula that still governs the Security Council veto today.
The promise that broke
The fight was over Eastern Europe, and Poland above all. Churchill's Britain had gone to war in 1939 over Poland's independence; Stalin had millions of Red Army troops already standing on Polish soil. The compromise was the 'Declaration on Liberated Europe,' in which Stalin pledged 'free and unfettered elections' in the countries his armies had overrun. He never delivered. Within three years, every state behind the advancing Soviet line, Poland, Hungary, Czechoslovakia, and the rest, had a communist government installed by Moscow. To Yalta's critics, that betrayal was baked in the moment Western leaders signed a promise they had no power to enforce.
Realism or betrayal
Ever since, 'Yalta' has been argued two ways. To its defenders, Roosevelt and Churchill simply recognized reality: the Red Army already held Eastern Europe, and no Western force was going to push it out short of a new war, so paper promises were the best that could be salvaged. To its critics, especially on the American right and among the exiled nations themselves, Yalta was a sellout that consigned a hundred million people to forty years of Soviet rule, a second Munich in which small nations were traded away for great-power peace.
Both readings hold truth, which is why the argument never dies. What is not in doubt is the through-line. The zones agreed at Yalta hardened into the Iron Curtain that Churchill named a year later. The satellite governments became the Warsaw Pact. And the Western refusal to accept Soviet expansion as permanent became the doctrine of containment that defined the next four decades. The palace on the Black Sea is now a museum, but the phrase it gave the language, a 'Yalta' deal, is still what leaders reach for whenever the strong sit down to carve up the weak.