The Iranian Prime Minister Mohammad Mosaddegh was removed from power On August 1953. The intelligence services of the U.S. and the U.K. were involved in the initiation and planning of the coup. This was to enable the two nations to retain their being in charge over the Iranian oil. The British initiated the plan in 1952 and President Eisenhower backed it immediately after taking office. The success of the mission as stated by the CIA's chief coup organizer was largely by chance. The U.S. secretary of state who served during this period stated that the coup was necessary for strategic reasons. These included issues related to oil and fears about communism. The Eisenhower government supported the coup even though it undermined the Iranian's political development.

The coup fell under the code name TP-AJAX, which is one of the several operations staged by the CIA to oust governments for the period of the cold war. The CIA prepared the strategy was well. First, they sent envoys to boost the Shah's courage. Secondly, they influenced the Iranians to initiate a series of bombings at different places. Those who carried out the bombings posed as members of the communist party. Finally, the CIA posed articles and cartoons in the Iranian newspapers in order to influence public opinion. The Iranians had no choice but to support the Shah after CIA created unrest in Iran.

On August 19, 1953, pro-Shah demonstrators being supported by the CIA marched through Tehran to the centre of the city. The demonstrators included military and police personnel. They clashed with the prime ministers supporters and more than 200 people died in the subsequent violence. Ousting the prime minister became inevitable. The CIA's developing the coup recruited royalist military personnel and selected the prime ministers substitute. At around 5:30 p.m. general Fazlollah Zahedi declared that he was the new prime minister. Immediately after the coup, CIA officials directed $5 million to Iran to assist the new government establish itself on power. The Shah consolidated power and ruled for 26 years under close relationship with the United States.