Background and causes of the Iranian Revolution

The Iranian Revolution was a populist, nationalist and Shi'a Islamic revolution that replaced a dictatorial monarchy with a theocracy based on "Guardianship of the Islamic Jurists" (or velayat-e faqih).

Its causes – why the Shah (Mohammad Reza Pahlavi) was overthrown and why he was replaced by an Islamic Republic – are the subject of historical debate. The revolution was in part a conservative backlash against the westernization and secularization efforts of the Western-backed Shah, and a more popular reaction to social injustice and other shortcomings of the . The Shah was perceived by many Iranians as beholden to – if not a puppet of – non-Muslim Western powers (in particular the United States) whose culture was contaminating that of Iran. The Shah's regime was seen as oppressive, brutal, corrupt and extravagant; it also suffered from basic functional failures, like overly ambitious economic programs that brought economic bottlenecks, shortages and inflation.

Shi'a clergy (or Ulema,) have had a significant influence in Iran. The clergy first showed themselves to be a powerful political force in opposition to Iran's monarch with the 1891 Tobacco Protest boycott that effectively destroyed an unpopular concession granted by the shah giving a British company a monopoly over buying and selling Tobacco in Iran. To some the incident demonstrated that the Shia ulama were "Iran's first line of defense" against colonialism.

The dynasty that the revolution overthrew – the Pahlavi dynasty – was known for its , its focus on modernization and Westernization and for its disregard for religious and democratic measures in Iran's constitution.

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