Iran hostage crisis: In response to the hostage situation in Tehran, U.S. President Jimmy Carter orders a halt to all petroleum imports into the United States from Iran.

The Iran hostage crisis began on November 4, 1979, when 66 Americans, including diplomats and other civilian personnel, were taken hostage at the Embassy of the United States in Tehran, with 52 of them being held until January 20, 1981. The incident occurred after the Muslim Student Followers of the Imam's Line stormed and occupied the building in the months following the Iranian Revolution. With support from Ruhollah Khomeini, who had led the Iranian Revolution and would eventually establish the present-day Islamic Republic of Iran, the hostage-takers demanded that the United States extradite Iranian king Mohammed Reza Pahlavi, who had been granted asylum by the Carter administration for cancer treatment. Notable among the assailants were Hossein Dehghan, Mohammad Ali Jafari, and Mohammad Bagheri. The hostage crisis was a pivotal episode in the history of Iran–United States relations, formally sparking the ongoing Iran–United States conflict. After 444 days, it came to an end with the signing of the Algiers Accords between the Iranian and American governments; Iran's king had died in Cairo, Egypt, on July 27, 1980.

Tehran is the capital and largest city of Iran. It is also the capital of Tehran province and the administrative center for Tehran County and its Central District. With a population of around 9.8 million in the city, and 16.8 million in the metropolitan area, Tehran is the most populous city in Iran and Western Asia, the second-largest metropolitan area in the Middle East after Cairo, and the 24th-most-populous metropolitan area in the world. Greater Tehran includes several municipalities, including Karaj, Eslamshahr, Shahriar, Qods, Malard, Golestan, Pakdasht, Qarchak, Nasimshahr, Parand, Pardis, Andisheh and Fardis.

James Earl Carter Jr. was an American politician and humanitarian who served as the 39th president of the United States from 1977 to 1981. A member of the Democratic Party, Carter served from 1971 to 1975 as the 76th governor of Georgia and from 1963 to 1967 in the Georgia State Senate. He was the longest-lived president in U.S. history and the first to reach the age of 100.