was the Shah of Iran from 1941 to 1979, also a period of tumultuous change in the world oil market. With Iran's great oil wealth, Pahlavi became the pre-eminent leader of the Middle East. In 1979, the religious opposition, lead by Ayatollah Ruhollah Khomeini, drove the shah into exile. Khomeini sought the capture of the shah, and when it was learned that he had been admitted into the United States for medical treatment, Iran's response was the start of the hostage crisis at the U.S. embassy in Teheran. This crisis contributed to a sharp rise in oil prices that eventually triggered a global recession. Once the Shah's course of treatment had finished, the American government, eager to avoid further controversy sent Pahlavi out of the country. He was welcomed by President Anwar Sadat of Egypt, and remained there until his death.