1907 Introduction of constitution which limits the royal absolutism of past dynasties that ruled Persia over the previous five centuries.

1921 22 February - Military commander Reza Khan seizes power.

1923 - Reza Khan becomes prime minister.

1925 12 December - Parliament, in a constituent assembly, vote to vest the crown of Iran in Reza Shah Pahlavi.

1926 25 April - The coronation takes place and the Pahlavi era begins. Mohammad Reza, the Shah's eldest son, is proclaimed Crown Prince.

1935 - Formerly known as Persia, Iran is adopted as the country's official name.

Shah installed

1941 - The Shah's pro-Axis allegiance in World War II leads to the Anglo-Russian occupation of Iran and the deposition of the Shah in favour of his son, Mohammad Reza Pahlavi.

1950 - Ali Razmara becomes prime minister and is assassinated less than nine months later. He is succeeded by the nationalist, Mohammad Mossadeq.

1951 April - Parliament votes to nationalise the oil industry. The Anglo-Iranian Oil Company is unable to continue operations and as a result Britain boycotts the purchase of Iranian oil. A power struggle between the Shah and Mossadeq ensues.

1953 22 August - With the help of western backing, mainly due to oil interests in the country, the Shah overthrows Mossadeq in a coup d'etat staged by General Fazlollah Zahedi.

Campaign to modernise

1963 26 January - The Shah embarks on a campaign to modernise and westernise the country. He launches the 'White Revolution', a programme of land reform and social and economic modernization. During the late 1960's the Shah became increasingly dependent on the Secret Police (SAVAK) in controlling those opposition movements critical of his reforms.

1978 September - The Shah's policies alienate the clergy and his authoritarian rule leads to riots, strikes and mass demonstrations. Martial law is imposed.

Shah exiled, Khomeini returns

1979 16 January - As the political situation deteriorates, the Shah and his family are forced into exile.

1979 1 February - The Islamic fundamentalist, Ayatollah Ruhollah Khomeini, returns to Iran following 14 years of exile in Iraq and France for opposing the regime.

1979 1 April - The Islamic Republic of Iran is proclaimed following a referendum.

1979 4 November - Islamic militants take 52 Americans hostage inside the US embassy in Tehran. They demand the extradition of the Shah, in the US at the time for medical treatment, to face trial in Iran.

1980 25 January - Abolhasan Bani-Sadr is elected the first President of the Islamic Republic. His government begins work on a major nationalization programme.

1980 27 July - The exiled Shah dies of cancer in Egypt.

Iran-Iraq war

1980 22 September - Iraq invades Iran following border skirmishes and a dispute over the Shatt al-Arab waterway. This marks the beginning of a war that will last eight years.

1981 20 January - The American hostages are released ending 444 days in captivity.

1981 22 June - Bani-Sadr is dismissed, he later flees to France.

1985 - After the US and Soviet Union halted arms supplies, the US attempted to win the release of hostages in Lebanon by offering secret arms deals, this would later become known as the Iran-Contra affair.