Mohammad Mosaddegh in the context of "1953 Iranian coup d'état"

Mohammad Reza Pahlavi (Persian: محمدرضا پهلوی [mohæmˈmæd reˈzɒː pæhlæˈviː]) (26 October 1919 – 27 July 1980) was the Shah of Iran from 1941 to 1979. He succeeded his father Reza Shah and ruled the Imperial State of Iran until he was overthrown by the 1979 Islamic Revolution led by Ruhollah Khomeini, which abolished the Iranian monarchy to establish the Islamic Republic of Iran. In 1967, he took the title Shahanshah (lit. 'King of Kings'), and also held several others, including Aryamehr (lit. 'Light of the Aryans') and Bozorg Arteshtaran (lit. 'Grand Army Commander'). He was the second and last ruling monarch of the Pahlavi dynasty.

During World War II, the Anglo-Soviet invasion of Iran forced the abdication of Reza Shah and succession of Mohammad Reza Shah. During his reign, the British-owned oil industry was nationalized by the prime minister Mohammad Mosaddegh, who had support from Iran's national parliament to do so; however, Mosaddegh was overthrown in the 1953 Iranian coup d'état, which was carried out by the Iranian military under the aegis of the United Kingdom and the United States. Subsequently, the Iranian government centralized power under the Shah and brought foreign oil companies back into the country's industry through the Consortium Agreement of 1954.

The Anglo-Persian Oil Company (APOC; Persian: شرکت نفت ایران و انگلیس) was a British company founded in 1909 following the discovery of a large oil field in Masjed Soleiman, Persia (Iran). The British government purchased 51% of the company in 1914, gaining a controlling number of shares, effectively nationalizing the company. It was the first company to extract petroleum from Iran. In 1935 APOC was renamed the Anglo-Iranian Oil Company (AIOC) when Reza Shah formally asked foreign countries to refer to Persia by its endonym Iran.

In 1954, it was renamed again to The British Petroleum Company, one of the antecedents of the modern BP public limited company. The government of Mohammad Mosaddegh nationalized the company's local infrastructure assets and gave the new company the name National Iranian Oil Company.

Relations between Iran and the United States in modern day are turbulent and have a troubled history. They began in the mid-to-late 19th century, when Iran was known to the Western world as Qajar Persia. Persia was very wary of British and Russian colonial interests during the Great Game. By contrast, the United States was seen as a more trustworthy foreign power, and the Americans Arthur Millspaugh and Morgan Shuster were even appointed treasurers-general by the Shahs of the time. During World War II, Iran was invaded by the United Kingdom and the Soviet Union, both US allies, but relations continued to be positive after the war until the later years of the government of Mohammad Mosaddegh, who was overthrown by a coup organized by the Central Intelligence Agency and aided by MI6. This was followed by an era of close alliance between Shah Mohammad Reza Pahlavi's authoritarian regime and the US government, Iran being one of the US's closest allies during the Cold War, which was in turn followed by a dramatic reversal and disagreement between the two countries after the 1979 Iranian Revolution.

The two nations have had no formal diplomatic relations since 7 April 1980. Instead, Pakistan serves as Iran's protecting power in the United States, while Switzerland serves as the United States' protecting power in Iran. Contacts are carried out through the Iranian Interests Section of the Pakistani Embassy in Washington, D.C., and the US Interests Section of the Swiss Embassy in Tehran. In August 2018, Supreme Leader of Iran Ali Khamenei banned direct talks with the United States. According to the US Department of Justice, Iran has since attempted to assassinate US officials and dissidents, including US president Donald Trump.