a dangerous international event in 1979-81, when Iranian students took 66 Americans from the US Embassy in Tehran and kept them as prisoners for more than 14 months. They demanded that the former Shah of Iran should be sent back to Iran from the US for trial. The US President, Jimmy Carter, ordered a rescue attempt in April 1980, but it failed. The crisis was an important reason for Carter's losing the 1980 election to Ronald Reagan. The prisoners were released on 20 January 1981, the day on which Reagan became President.