The Iranian Revolution of 1979 overthrew the Pahlavi dynasty and established Iran as an Islamic republic. Led by Ayatollah Khomeini, the revolution erupted amid widespread public dissatisfaction with the Westernization policies of Shah Mohammad Reza Pahlavi and the brutal methods of his secret police. Protests and strikes paralyzed the country in late 1978. In early 1979, the Shah fled Iran and Khomeini returned from exile, consolidating control and declaring an Islamic republic. The revolution had major social, political, and economic impacts both within Iran and internationally, including the U.S. hostage crisis.