The Anglo-Soviet invasion of Iran or Anglo-Soviet invasion of Persia was the joint invasion of the neutral Imperial State of Iran by the United Kingdom and the Soviet Union in August 1941. The two powers announced that they would stay until six months after the end of the war with their enemy Nazi Germany, which turned out to be 2 March 1946. On that date the British began to withdraw, but the Soviet Union delayed until May, citing "threats to Soviet security".

Pahlavi Iran, officially the Imperial State of Persia until 1935 and the Imperial State of Iran from 1935 to 1979, was the Iranian state under the rule of the Pahlavi dynasty. The Pahlavi dynasty was created in 1925 and lasted until 1979, when it was ousted as part of the Islamic Revolution, which ended Iran's continuous monarchy and established the current Islamic Republic of Iran.