The 444 days in which American embassy workers were held captive by Iranian revolutionaries after young Muslim fundamentalists overthrew the oppressive regime of the American-backed shah, forcing him into exile. These revolutionaries triggered an energy crisis by cutting off Iranian oil. The crisis began when revolutionaries stormed the American embassy, demanding that the United States return the shah to Iran for trial. The episode was marked by botched diplomacy and failed rescue attempts by the Carter Administration. After permanently damaging relations between the two countries, the crisis ended with the hostage's release the day Ronald Reagan became president