The Iranian Revolution establishes an Islamic theocracy under the leadership of Ayatollah Ruhollah Khomeini.

Sayyid Ruhollah Musavi Khomeini (UK: khom-AY-nee, US: khohm-; Persian: [uhollhe xomejni] (listen); 17 May 1900 3 June 1989), also known as Ayatollah Khomeini, was an Iranian political and religious leader who served as the first supreme leader of Iran from 1979 until his death in 1989. He was the founder of the Islamic Republic of Iran and the leader of the 1979 Iranian Revolution, which saw the overthrow of Shah Mohammad Reza Pahlavi and the end of the Persian monarchy. Following the revolution, Khomeini became the country's first supreme leader, a position created in the constitution of the Islamic Republic as the highest-ranking political and religious authority of the nation, which he held until his death. Most of his period in power was taken up by the IranIraq War of 19801988. He was succeeded by Ali Khamenei on 4 June 1989.

Khomeini was born in Khomeyn, in what is now Iran's Markazi Province. His father was murdered in 1903 when Khomeini was two years old. He began studying the Quran and Arabic from a young age and was assisted in his religious studies by his relatives, including his mother's cousin and older brother.

Khomeini was a marja ("source of emulation") in Twelver Shia Islam, a Mujtahid or faqih (an expert in Sharia) and author of more than 40 books. He spent more than 15 years in exile for his opposition to the last shah. In his writings and preachings he expanded the theory of welayat-el faqih, the "Guardianship of the Islamic Jurist (clerical authority)", to include theocratic political rule by Islamic jurists. This principle, though not known to the wider public before the revolution, was appended to the new Iranian constitution after being put to a referendum. According to The New York Times, Khomeini called democracy the equivalent of prostitution. Whether Khomeini's ideas are compatible with democracy and whether he intended the Islamic Republic to be democratic is disputed. He was Time magazine's Man of the Year in 1979 for his international influence, and Khomeini has been described as the "virtual face of Shia Islam in Western popular culture". In 1982, he survived one military coup attempt. Khomeini was known for his support of the hostage takers during the Iran hostage crisis, his fatwa calling for the murder of British Indian novelist Salman Rushdie, and for referring to the United States as the "Great Satan" and the Soviet Union as the "Lesser Satan". Khomeini has been criticized for these acts and for human rights violations of Iranians (including his ordering of

attacks against demonstrators, execution of thousands of political prisoners, war criminals and prisoners of the IranIraq War).Khomeini has also been lauded as a "charismatic leader of immense popularity", a "champion of Islamic revival" by Shia scholars, who attempted to establish good relations between Sunnis and Shias, and a major innovator in political theory and religious-oriented populist political strategy. Khomeini held the title of Grand Ayatollah and is officially known as Imam Khomeini inside Iran and by his supporters internationally. He is generally referred to as Ayatollah Khomeini by others. In Iran, his gold-domed tomb in Tehran's Behesht-e Zahr cemetery has become a shrine for his adherents, and he is legally considered "inviolable", with Iranians regularly punished for insulting him. A cult of personality developed around Khomeini after the Iranian Revolution.

The Iranian Revolution (Persian: انقلاب ایران, romanized: Enqelâb-e Irân, pronounced [ʔeɴɢeˌlɒːbe ʔiːɾɒːn]), also known as the Islamic Revolution (Persian: انقلاب اسلامی, romanized: Enqelâb-e Eslâmī) was a series of events that culminated in the overthrow of the Pahlavi dynasty under Shah Mohammad Reza Pahlavi, and the replacement of his government with an Islamic republic under the rule of Ayatollah Ruhollah Khomeini, a leader of one of the factions in the revolt. The revolution was supported by various leftist and Islamist organizations.After the 1953 Iranian coup d'état, Pahlavi had aligned with the United States and the Western Bloc to rule more firmly as an absolute monarch. He relied heavily on support from the United States to hold on to power which he held for a further 26 years. This led to the 1963 White Revolution and the arrest and exile of Ayatollah Khomeini in 1964. Amidst massive tensions between Khomeini and the Shah, demonstrations began in October 1977, developing into a campaign of civil resistance that included both secular and religious elements. The protests rapidly intensified in 1978 as a result of the burning of Rex Cinema which was seen as the trigger of the revolution.On 16 January 1979, the Shah had fled Iran in exile as the last Persian monarch, leaving his duties to a regency council and Shapour Bakhtiar, who was an opposition-based prime minister. Ayatollah Khomeini was invited back to Iran by the government, and returned to Tehran to a greeting by several thousand Iranians. The royal reign collapsed shortly after, on 11 February, when guerrillas and rebel troops overwhelmed troops loyal to the Shah in armed street fighting, bringing Khomeini to official power. Iran voted by national referendum to become an Islamic republic on 1 April 1979 and to formulate and approve a new theocratic-republican constitution whereby Khomeini became supreme leader of the country in December 1979.

The revolution was unusual for the surprise it created throughout the world. It lacked many of the customary causes of revolution (defeat in war, a financial crisis, peasant rebellion, or disgruntled military); occurred in a nation that was experiencing relative prosperity; produced profound change at great speed; resulted in the exile of many Iranians; and replaced a pro-Western absolute monarchy with an anti-Western theocracy based on the concept of velayat-e faqih (or Guardianship of the Islamic Jurists). In addition to these, the revolution sought a region-wide Shia revival, and an uprooting of the existent dominant Arab Sunni hegemony in the Middle East.