1953 Iranian coup d'état

In 1953, there was an Iranian coup d'état to remove the Prime Minister of Iran, Mohammad Mossadeq, from power. The coup d'état was nicknamed Operation Ajax. The coup was planned by the CIA and Britain's MI6 in August 1953.
Causes.
In 1951, Mossaddeq was the chairman of Iran's Oil Committee. He was highly supported by the people of Iran. At that time, Shah Mohammad Reza Pahlavi was in power. The Majlis (Iranian Parliament) voted for a law to "nationalize" (take the company away from the people who owned it and make it owned by the government) the Anglo-Iranian Oil Company, an oil company in Iran.
Mossaddeq was elected Prime Minister of Iran in April 1951. His first action as Prime Minister was to put the oil nationalization in place.
The British government had a plan for a coup d'etat to remove Mossadeq from power. They managed to get the United States CIA to help with the coup. The coup was planned by Monty Woodhouse. It was carried out by MI6 and the CIA, and led by General Fazlollah Zahedi, who later went into exile.
Later.
Mossaddeq was replaced by Fazlollah Zahedi, but Mossaddeq refused to step down. A military dictatorship was put in place. Shah Pahlavi, known for treating the people of Iran badly, was put back in power. (Pahlavi was in power before this, but he was forced to put Mossadeq back in power at the time.) This made the people angry. They would later start the Iranian Revolution in 1979. The revolution put the Ayatollah Khomeini in power.