7th century BC: Media a Great Power.
Around 600 BC: Zarathustra lives in eastern Iran.
6th century BC: Persians win the whole of Iran and the Middle East (under kings like Cyrus 2, Kambyses, Dareios 1). The Persian Empire rules from the capital Perspolis.
5th century BC Wars against the Greeks. Land is gained all the way to the Ægian Sea.
4th century BC: The structure of the state dissolves.
330 BC: Alexander the Great warfare subjugates the northern and most populated parts of Iran.

324 BC: The returning campaign of Alexander's takes control over the southern parts of Iran.
3rd century BC: After years of fighting at the aftermath of Alexander, the Partians become the new rulers, and their kingdom becomes one of the big powers in the Middle East.
225 AD: Kingdom of the Sassinids, a new grand era. Zoroastrianism becomes the state religion.
630s, 640s: Arabs conquer Iran. From this time on, the people of Iran are slowly converting into Islam.
1000- 1500: Time of Seljuks and the Mongols.
1501-24: Ismail 1 of the Safavide dynasty establishes an Iranian national state. Shi'i Islam is defined as the religion of the state. Major efforts are put into winning Sunni population over to the new creed.
1588-1629: Abbas 1. Iran strong in politics and in cultural achievements.
1722: Afghan occupation of central parts of Iran.
1724: Russian and Turkish interference. The two countries divide Iran.
1736: The puppet ruler of Russia and Turkey became strong enough to ascend to power under the name Nadir Shah in 1736.
1739: Afghanistan conquered, and Delhi sacked. Enormous loot is brought back to Iran.
1747: Nadir Shah is assassinated, and his kingdom is fragmented. Southern Iran sees prosperity, under the Zand dynasty.
1794: Qajar dynasty established. This lasts until 1925.
1840: Leader of the Shi'i Isma'ili group, Aga Khan, escapes to India after a failed rebellion against the Shah.
1857: Persia recognizes Afghanistan after British military intervention.
1891: The tobacco boycott, which opposed British monopoly on all trade with tobacco in Persia. These actions were crowned with success the year after. The opposition groups remained strong after this, and became central in Iranian politics 15 years later.
1906: The constitutional revolution.
1907: Russia and Britain divides Persia into protecting zones.
1914-18: Persia is neutral in World War 1, but becomes nonetheless a battleground, where the oil of the country was the goal.
1919-21: Due to the threat from Bolshevik Russia, Persia becomes British protectorate for a period.
1921: Riza Khan Pahlavi establishes a new government, with himself as war minister and he take over Arab Stan , which is an Arabic Kingdom in the south East of Iran. Sheikh Khazal was assassinated by the British and Iranian secret service and his country was taken over by Shah Riza.
1923: Riza Khan takes the position as prime minister.
1925: Riza Khan is elected Shah. He starts a Westernization after Turkish model (Atatürk).
1935: Persia changes its name to Iran.
1936: The women around the Shah stops wearing veils. This is gradually adopted by other women of Iran.
1939: German infiltration. Shah Riza conducts a politics friendly towards the interests of the Axis states.
1941: Allied occupation of Iran. Shah Riza abdicates, and his son Muhammad Riza Pahlavi takes over the position as Shah.
1943: Iran joins the Allied side in the war.
1947: Start of a US-Iranian cooperation in developing the oil industry.
1949: Iran becomes a constitutional monarchy.
1951: Nationalization of the oil industry.
1953: The Prime Minister, Muhammad Musaddiq, is overthrown with American aid. Musaddiq had been governing with unlimited power for some time, and had been propagating for the Shah to be deposed.
1950s: Iran opens up for cooperation with European countries and USA in the oil industry.
1959: Defense agreement with USA.
1962-66: Large estates are divided into smaller farms and given to 4 million families. Many of these estates had been religious endowment, waqf, so these reforms were met by fierce protests from the religious leaders.
1971: Iran occupies some Iraqi islands in the Persian Gulf. Iraq breaks all diplomatic connections with Iran.
1975: The dispute over land between Iran and Iraq is settled in an agreement. Iran keeps the occupied territory.
1970s: Despite economical growth, there is much opposition towards the Shah, and he uses the secret police, the Savak, to control the country.
1978: Strong Shi'i opposition towards the Shah, and the country comes close to a situation of civil war. The opposition is lead by Ayatollah Khomeni, who lives in exile in France. His message is transmitted through music cassettes, which are smuggled into Iran in small numbers, and then duplicated, and spread all around the country.
1979 January 16: The Shah leaves Iran, as his new government can't control the situation in the country anymore.
— February 1: Khomeni returns to Iran. A period of antagonism starts. Processes against the supporters of the Shah starts, and hundreds are executed. Many demonstrations are held in protest to the new rules, like extreme regulations on women's dress.
— March 30: Referendum on the new Iranian constitution is held, where the Islamic republic is chosen.
— November: Iranian students storm the US embassy, taking 70 people, the majority Americans, as hostages. 18 are released before the end of November. This conflict would last more than one year, and has more than anything else formed the West's image of the present regime of Iran as an anti-Western one.
1980: Abolhassan Beni Sadr is elected for president. Iraq invades Iran, in the belief that Iran is too weak military to fight back. Iraq is claiming territories inhabited by Arabs, as well as territory occupied by Iran in 1971. Some battles are won in the favor of Iraq, but Iran is fast preparing to fight back.
1981 January 20: The hostages in the US embassy are released, after long negotiations, where USA concedes to transfer money, as well as export military equipment to Iran. This year sees the height of a conflict between the ulama and Beni Sadr.
— June: Beni Sadr is removed from power by Khomeni, and flees to France in July. Here he establishes the National Council of Resistance in cooperation with Mujahidin-e-Khalq.
1982: The Iraqi forces are driven out of Iran. The war extends to shooting of boats in the Persian Gulf, in an attempt to hurt the other country's oil exports.
1987: The fights between Iran and Iraq are reduced to a minimum.
1988 August 20: A cease-fire is signed between Iran and Iraq.
1989 June: A Fatwa is issued by Khomeni against the British author Salman Rushdie, as a reaction to the presentation of Islam and Muhammad in his book Satanic Verses, published the year before. Soon after, Khomeni dies.
— July: Ali Akbar Hashemi Rafsanjani is elected president. Relations with Western countries are slightly improved.
1990: Earthquake in Caucasian regions that kills about 35,000 Iranians.
1990-91: Iran condemns both Iraq's invasion of Kuwait, and the allied forces actions towards Iraq.
1995: Total ban on trade with Iran is imposed by the USA.
1996: USA carries a law that any company, even non-US, investing in Iran and Libya, will be punished by American law if and when these act in USA.
— September: Considerable increase in the political and economical relations with Turkey.

1999: President Khatemi has started a new era of liberalization and opening up the country. Ties with US & European countries are improving. President Khatemi visits many European nations.