After the second world war, the occupation of the German and Austrian regions was managed by 4 major powers: France, the United Kingdom, the United States of America, and the Soviet Union. The goals of these powers was twofold.
The first was the purging of National Socialist elements from Germany. After the war, thousands of Nazis escaped capture by the allies, with many returning to their lives as civilians. The occupying forces were attempting to ensure that these individuals would not exert major influence, and that Nazism would not rise again in post-war Germany. Here's an interesting orientation video produced by the US army during the post-war occupation period: https://www.youtube.com/watch?v=e-EjnQwqbaQ
The second of these goals was the establishment of two new German states. The Soviet Union laid the ground work for what would become the communist German Democratic Republic in the late 1940s in the eastern half of Germany, while the allies established a market-liberal counterpart (the Federal Republic of Germany) in the west.
