Western countries, particularly the United States, were generally opposed to the Iranian Revolution of 1979. The revolution resulted in the overthrow of the Shah of Iran, a key U.S. ally in the region, and the establishment of an Islamic Republic led by Ayatollah Khomeini. Many Western countries, including the United States, viewed the Iranian Revolution as a threat to stability in the region and were concerned about the potential spread of Islamic fundamentalism. The takeover of the U.S. embassy in Tehran by Iranian militants and the subsequent hostage crisis further strained relations between Iran and the West.