Final answer:
Eastern Europe became an area of disagreement after WWII due to Cold War tensions. The region was carved into a communist bloc under Soviet influence, contrasting with Western capitalist democracies, leading to the creation of the Iron Curtain.
Step-by-step explanation:
After World War II, Eastern Europe became an area of disagreement and a focal point for Cold War tensions. Postwar diplomacy and ideological differences between capitalist Western Europe and communist Eastern Europe led to a divide marked by the Iron Curtain. The region fell under the influence of the Soviet Union which looked to establish a pro-Russian buffer zone, resulting in countries within Eastern Europe adopting communism and creating a point of contention with the capitalist nations of the West.
This disagreement was rooted in both the geopolitical aim of the Soviet Union to create a protective barrier and the Western powers' desire to spread democracy. The Iron Curtain manifested physically through structures like the Berlin Wall, and ideologically through the formation of opposing alliances such as NATO in the West and the Warsaw Pact in the East.