Defeating Germany gave the Allies a shared urgent goal. Once that enemy was gone, disputes about Germany and Eastern European governments became harder to contain.
The wartime alliance was cooperation against a common enemy, not agreement about how the world should be governed. Soviet leader Joseph Stalin also resented the delay in opening a major Western Front against Germany. At the Yalta and Potsdam conferences in 1945, Allied leaders discussed occupation and the postwar settlement. Agreements left difficult disputes: how much Germany should pay in reparations, meaning compensation for war damage, and whether Eastern Europeans could freely choose their governments. Rebuilding Germany could help European recovery but also revive a country the USSR feared.
Soviet-backed communist parties strengthened their control in Eastern Europe and restricted opposition. Western leaders saw this as breaking promises that people freed from Nazi rule could choose their future. Soviet leaders distrusted Western plans for Germany and feared losing control of neighbouring states. On 5 March 1946, former British prime minister Winston Churchill described an Iron Curtain across Europe. This was a metaphor for political division and Soviet control, not a physical wall he had built. The speech expressed an existing breakdown in trust; it did not create the division by itself.
Worked example: Why old differences mattered more after victory
The USA and USSR already had different systems while they fought Germany. Explain why cooperation then became harder.
- During the war, both needed to defeat Germany, so cooperation offered an immediate benefit despite mistrust.
- After victory, they still disagreed about whether neighbouring governments would be freely chosen or kept friendly to the USSR, and how Germany should recover.
- With the common enemy gone, these disputes mattered more than the old reason to cooperate. Ideology shaped their suspicions, while postwar decisions turned those suspicions into conflict.
Watch out for this
Churchill's Iron Curtain speech created the division of Europe in 1946.
Churchill was describing and warning about growing political division. The rivalry developed through decisions about governments, aid and security. The Berlin Wall was a later physical barrier, built in 1961.
Check your understanding
Why did defeating Germany make the alliance harder to maintain?
- Victory removed Soviet security fears, leaving only an argument about economic ideas.
- The common enemy disappeared while disagreements over governments, Germany and security remained.
- Ideological differences first emerged at the postwar conferences.