Reza Shah Pahlavi was an Iranian military officer and the founder of the Pahlavi dynasty. As a politician, he previously served as minister of war and prime minister of Qajar Iran and subsequently reigned as Shah of Pahlavi Iran from 1925 until he was forced to abdicate after the Anglo-Soviet invasion of Iran in 1941. He was succeeded by his eldest son, Mohammad Reza Shah. A modernizer, Reza Shah clashed with the Shia clergy, but also introduced many social, economic, and political reforms during his reign, ultimately laying the foundation of the modern Iranian State. Therefore, he is regarded by many as the founder of modern Iran.

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".