Four-power Vienna and the Austrian State Treaty

From 1945 Vienna was split into American, British, French and Soviet sectors, with the old centre patrolled jointly by 'four men in a jeep'. Its black market and agents of every side gave Graham Greene the setting for The Third Man. On 15 May 1955 the four powers signed the State Treaty at the Belvedere, their troops left, and that October Austria declared permanent neutrality.