The Allied occupation of Austria starts on April 27, 1945 as a result of the Vienna Offensive and ends with the Austrian State Treaty on July 27, 955.

Subsequent to the Anschluss, Austria had generally been recognized as constituent part of Nazi Germany.

In 1943 however, the Allies had agreed in the Declaration of Moscow that Austria would instead be regarded as the first victim of Nazi aggression, and treated as a liberated and independent country after the war.

In the immediate aftermath of the Second World War, Austria is divided into four occupation zones and jointly occupied by the United States, the Soviet Union, the United Kingdom, and France.

Vienna is similarly subdivided but the central district was collectively administered by the Allied Control Council.

Whereas Germany is divided into East and West Germany in 1949, Austria remains under joint occupation of the Western Allies and the Soviet Union until 1955; its status becomes a controversial subject in the Cold War until the warming of relations known as the Khrushchev Thaw.

After Austrian promises of perpetual neutrality, Austria is accorded full independence on May 15, 1955, and the last occupation troops leave on October 25 of this year.