The splitting of Europe into two different political and ideological spheres had started with the Russian revolution and the advance of communist ideas into the political life. During World War II the Soviet Union and Nazi Germany signed the Hitler-Stalin-Pact. They promised mutual renunciation of aggression, neutrality in wars with third parties and - in a secret minute - the partition of Europe into spheres of interest. After the German invasion the Soviet Union joined the Allies as one of the three big parties. Towards the end of World War II, beginning with the Tehran Conference in 1943, the Soviet Union started to follow its interests for a post-war order. For its support of the Allies in the fight against the Axis powers, it demanded the adjustment of the Polish-Soviet border (Curzon line) and the support of Yugoslavian communist partisans. The conferences of Jalta and Potsdam followed, determining the splitting of post-war Europe into two spheres of influence.
After the war many Eastern European countries fell under Soviet socialist influence, mostly belonging to the Warsaw Pact, while 'Western' countries from Norway to Turkey practised social or free market economy, most of them being part of the western defence alliance NATO.
Some European countries stayed out of the two alliances: Former Yugoslavia kept its full independence and Albania escaped Soviet influence in the 60s and aligned itself with China. West of the Iron Curtain Sweden, Finland, Ireland, Liechtenstein, Austria and Switzerland remained independent in a military sense and formed the so called 'non aligned nations'.
Economically the western states were organised in the European Community and the European Trade Association whereas the eastern states formed COMECON (Council for Mutual Economic Assistance 1949-1991).
Germany and Austria were separated into four zones of occupations (Soviet, American, British and French). In 1949 the Federal Republic of Germany and the German Democratic Republic were founded, in 1955 the Austrian State Treaty was signed and confirmed by the occupying powers - Austria declared its political neutrality. The following period of political tension, intensive armament on both sides and several proxy wars throughout the world was called the Cold War.
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