The United States allowed the Shah to come to America following the Iranian Revolution to receive medical treatment.
After his overthrow, the Shah was allowed to travel to the United States to receive medical treatment. The Islamist rebels demanded the United States to extradite the Shah back to Iran to judge him for crimes committed by his government during his reign over ordinary citizens with the help of his secret police, the SAVAK. In Iran, the asylum granted by the USA for the Shah was seen as an act of complicity, and originated the Iran Hostage Crisis, which lasted from November 1979 to January 1981.
