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Four-power Vienna

After the war, Vienna was part of Soviet-occupied Eastern Austria until September 1945. In September 1945, Vienna was divided into sectors by the four powers: the US, the UK, France, and the Soviet Union and supervised by an Allied Commission. The four-power occupation of Vienna differed in one key respect from that of Berlin: the central area of the city, known as the first district, constituted an international zone in which the four powers alternated control on a monthly basis. The control was policed by the four powers on a de facto day-to-day basis, the famous "four soldiers in a jeep" method. The Berlin Blockade of 1948 raised Western concerns that the Soviets might repeat the blockade in Vienna. The matter was raised in the UK House of Commons by MP Anthony Nutting, who asked: "What plans have the Government for dealing with a similar situation in Vienna? Vienna is in exactly a similar position to Berlin."

There was a lack of airfields in the Western sectors, and authorities drafted contingency plans to deal with such a blockade. Plans included the laying down of metal landing mats at Schönbrunn. The Soviets did not blockade the city. The Potsdam Agreement included written rights of land access to the western sectors, whereas no such written guarantees had covered the western sectors of Berlin. Also, there was no precipitating event to cause a blockade in Vienna. (In Berlin, the Western powers had introduced a new currency in early 1948 to economically freeze out the Soviets.) During the 10 years of the four-power occupation, Vienna became a hotbed for international espionage between the Western and Eastern blocs. In the wake of the Berlin Blockade, the Cold War in Vienna took on a different dynamic. While accepting that Germany and Berlin would be divided, the Soviets had decided against allowing the same state of affairs to arise in Austria and Vienna. Here, the Soviet forces controlled districts 2, 4, 10, 20, 21, and 22 and all areas incorporated into Vienna in 1938.

Barbed wire fences were installed around the perimeter of West Berlin in 1953, but not in Vienna. By 1955, the Soviets, by signing the Austrian State Treaty, agreed to relinquish their occupation zones in Eastern Austria as well as their sector in Vienna. In exchange they required that Austria declare its permanent neutrality after the allied powers had left the country. Thus they ensured that Austria would not be a member of NATO and that NATO forces would therefore not have direct communications between Italy and West Germany.

The atmosphere of four-power Vienna is the background for Graham Greene 's screenplay for the film The Third Man (1949). The film's theme music was composed and performed by Viennese musician Anton Karas using a zither. Later he adapted the screenplay as a novel and published it. Occupied Vienna is also depicted in the 1991 Philip Kerr novel, A German Requiem.