After World War II, the Western allies and the Soviet Union did the following:
1) Split up Germany into two different parts- Germany was split up into East and West Germany. East Germany was controlled by the Soviet Union. West Germany was controlled by the United States, France, and Great Britain.
2) Split up the capital of Germany (Berlin) into two different parts- East Berlin was controlled by the Soviet Union and West Berlin was controlled by the Western allies.
3) Broke up Nazi party and punished leaders- Leaders of the Nazi Party were put on trial thanks to the United Nations. These hearings, known as the Nuremberg Trials, helped to punish German officers responsible for the deaths of millions of innocent European citizens.