World War II
After the war, the United Nations was set up to develop support between countries and to prevent future wars.  The Cold War by the major winners soon started, but they did not fight each other in an actual war. The decolonization of Asia and Africa (where many places controlled by European countries were given their independence) happened as well since Europe had been weakened by the war. Economic recovery and political integration (the process of uniting countries) were among other results of the war.