550-330 B.C.E.

Achaemenid dynasty rules the first Persian Empire. The city of Persepolis, was founded in 518 B.C.E.

1914-1918

Iran declares neutrality during World War I.

1923–1926

Reza Khan is named prime minister, then is crowned Reza Shah Pahlavi. Mohammad Reza, the Shah's eldest son, is proclaimed Crown Prince.

1935-1941

Persia is re-named Iran. Iran is occupied by an Anglo-Russian coalition during World War II; Reza Shah is deposed and replaced by his son Reza Pahlavi.

1950–1953

Nationalist leader Mohammad Mossadeq becomes Prime Minister. Parliament nationalizes the oil industry. American and British intelligence services overthrow Mossadeq and restore the Shah to power.

1963–1978

The Shah undertakes national development, including land reform, social and economic modernization. The secret police (SAVAK) gain power.

1978–1979

Opposition to the Shah’s rule grows among Shi’i religious figures. Strikes and mass demonstrations prompt imposition of martial law. The Iranian Revolution ousts the Shah. Ayatollah Ruhollah Khomeini (1902-1989) returns to Iran from exile, proclaims the Islamic Republic of Iran, and  becomes Supreme Leader. Iranian militants take 52 Americans hostage inside the US embassy in Tehran, who are released after 444 days in captivity, in 1981.

1980-1989

Shah dies of cancer in Egyptian exile. Saddam Hussein begins the eight-year Iran-Iraq War. Ayatollah Khomeini dies, and President Khamene'i becomes new supreme leader.

1997-2001

Reformist Mohammad Khatami is elected President. In 2000, conservatives are defeated in parliamentary elections for the first time since the revolution.

2002 – 2007

Russians construct a nuclear reactor at Bushehr, and Iran submits to International Atomic Energy Agency inspection as signatory to the 1970 international Treaty on the Non-Proliferation of Nuclear Weapons. Amid accusations that Iran plans to build nuclear weapons, sanctions are implemented against Iran.

2005-2009

Mahmoud Ahmadinejad is elected President in 2005 and conservatives win over two-thirds of seats in parliamentary elections. In 2009, demonstrations challenge Mahmoud Ahmadinejad’s re-election and are suppressed by government forces.

2009–2012

Iran admits to building a uranium enrichment plant near Qom. International pressure against the Iranian nuclear program continues with boycotts and other sanctions.

2013

Hassan Rouhani is elected President and takes office.