In the decades before the Islamic revolution of 1979, Iran was ruled by the Shah whose dictatorship repressed dissent and restricted political freedoms. But he also he pushed the country to adopt Western-oriented secular modernization, allowing some degree of cultural freedom.
Under the Shah's rule, Iran's economy and educational opportunities expanded. Britain and the US counted Iran as their major ally in the Middle East, and the Shah forcefully industrialized large segments of the country. However, the Shah's increasingly authoritarian measures and his eventual dismissal of multiparty rule set the stage for the infamous revolution.

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Iran after The revolution
The revolution was unusual for the surprise it created throughout the world it lacked many of the customary causes of revolution (defeat at war, a financial crisis, peasant rebellion, or disgruntled military), occurred in a nation that was experiencing relative prosperity, produced profound change at great speed, was massively popular, resulted in the exile of many Iranians, and replaced a pro-Western authoritarian monarchy with an anti-Western authoritarian theocracy based on the concept of Guardianship of the Islamic Jurists (or velayat-e faqih)

Revolution

Funny things