World War II, the most shocking historical and demographic catastrophe in European history, undermined Europe's position in the world. About 40 million Europeans perished, and huge parts of the continent were left in ruins. At their postwar nadir, the combined Gross Domestic Product of Austria, Germany, Italy, Belgium, and France had declined to less than half its prewar level. Bombing and street fights fatally destroyed Berlin, Dresden, Hamburg, Leningrad, Warsaw, and Budapest. The population of the Soviet Union, Poland, and Yugoslavia was literally decimated, the European Jewry was nearly eliminated, and tens of millions of people were uprooted. Devastation, inflation, and starvation left Europe on its knees.

Moreover, the clouds of a rising new conflict darkened the horizon at the end of the war. A creeping Cold War, with conflict and confrontation between wartime allies, brought uncertainty and fear to the shocked continent. The Soviet Union occupied and soon sovietized the countries east of the River Elbe that it had liberated from Nazi German and local fascist rule. The Eastern half of the continent was isolated from the West by a Soviet-type economic system and social-political regime and formed separate Soviet-led economic and military arrangements. In terms of trade, travel, and communication, exchange between the two halves of Europe was limited to a minimum. Several people believed that Stalin wanted to enlarge his buffer zone by occupying additional parts of the continent.