|Unrest broke out after opposition leaders alleged fraud in presidential polls [GALLO/GETTY]
The re-election of Mahmoud Ahmadinejad after presidential polls on June 12 was heavily disputed by two defeated candidates, who claimed there had been mass fraud.
The dispute of the result brought tens of thousands of supporters of the reformist candidates out onto the streets to demand that the result be annulled and there have been sporadic protests every since.
June 13 - Authorities say that Mahmoud Ahmadinejad, the incumbent, has won the election with nearly 63 per cent of vote. Mir Hossein Mousavi, who polled 34 per cent of the vote, describes the result a "dangerous charade" and thousands of protesters clash with police.
June 14 - Mousavi asks the powerful Guardian Council, which has the power of veto over government legislation and can bar candidates from elections, to annul the results.
June 15 - At least seven people are killed during a march by Mousavi supporters in Tehran, state media says. Protests break out in other cities.
June 16 - Thousands of pro-Mousavi demonstrators march in northern Tehran. Authorities ban foreign journalists from leaving their offices to cover the street protests.
June 19 - Ayatollah Ali Khamenei, Iran's supreme leader, says that the protest leaders will be held responsible for any bloodshed if demonstrations over election continue. He says Ahmadinejad won the polls fairly by 11 million votes.
June 20 - Riot police are deployed to disperse groups of several hundred Iranians who have gathered across Tehran.
A suicide bomber blows himself up near the shrine of Ayatollah Ruhollah Khomeini, the leader of the 1979 Islamic revolution, in Tehran, Iran's semi-official Mehr news agency reports.
State television says 450 people are detained during clashes in the capital in which 10 people are killed, including Neda Agha-Soltan. Graphic footage of her death is seen around the world on the internet and she becomes a symbol of the opposition movement.
June 23 - Guardian Council again rules out annulment of the poll, saying there have been no major irregularities. Riot police and Basij militia in Tehran prevent planned protests.
Barack Obama, the US president, says the United States is "appalled and outraged" by Iran's crackdown on opposition supporters.
Britain expels two Iranian diplomats after two of its own are expelled from Iran.
June 26 - Ahmad Khatami, a member of the Assembly of Experts, an elected body which appoints and monitors the performance of the supreme leader, calls for the execution of leading "rioters".
June 28 - Authorities detain several local British embassy staff for alleged involvement in the unrest. Britain calls the arrests "harassment and intimidation" and demands their release.
July 17 - Clashes erupt between police and opposition protesters for the first time in weeks in Tehran after Akbar Hashemi Rafsanjani, a former president, declares that Iran is in crisis.
July 20 - Mohammad Khatami, another former president, calls for a referendum on the legitimacy of the government.
July 30 - Clashes erupt after hundreds of Mousavi supporters gather to mourn Neda Agha-Soltan at the Behesht-e Zahra cemetery. Hundreds of police fire teargas to disperse protesters from nearby streets.
August 1 - Iran puts a number of prominent individuals on trial charged with trying to overthrow the religious establishment.
August 3 - Khamenei formally approves the second term presidency of Ahmadinejad.
August 5 - Ahmadinejad is sworn in by parliament.
August 8 - A court charges a French woman, two Iranians working for the British and French embassies in Tehran and dozens of others with spying and aiding a Western plot to overthrow the system of religious rule.
August 25 - A prosecutor demands "maximum punishment" for Saeed Hajjarian, a senior reformist activist, accused of acting against national security.
September 3 - Parliament approves most of Ahmadinejad's cabinet.
September 9 - Mousavi says on a website the detention of Alireza Hosseini Beheshti and Morteza Alviri, two senior reformists, was a "sign of more horrendous events to come".
September 11 - The Etemad-e Melli website says Mohammad Ozlati-Moghaddam, a member of Mousavi's campaign headquarters staff ahead of the election, has been detained.
October 18 - Mousavi pledges to press ahead with efforts to change Iran despite a crackdown on protests, his website reports.
October 28 - Khamenei says it is a crime to cast doubt on the June election, which the opposition says was rigged.
November 4 - Police clash with Mousavi supporters in Tehran on the 30th anniversary of the storming of the US embassy.
November 22 - Mohammad Ali Abtahi, a reformist former vice-president, who was arrested after the election, is sentenced to six years in jail, Iranian newspapers report. He is released on bail pending an appeal.
December 19 - Grand Ayatollah Hossein Ali Montazeri, Iran's most senior dissident cleric, dies. The opposition holds demonstrations as he is buried.
December 23 - The home of Grand Ayatollah Yusuf Sanei, a senior reformist cleric, is attacked, an opposition website reports.
December 24 - Iran bans memorial services for Montazeri with the exception of those in his birthplace and Qom.
December 27 - Police confirm that five people are killed in clashes between police and protesters which coincide with the religious event of Ashoura. There are reports that Seyyed Ali Mousavi, the nephew of opposition leader Mir Hossein Mousavi, is killed.
December 30 - Tens of thousands of Iranians take to the streets across Iran for a series of state-sponsored rallies designed as a show of strength following the pro-opposition demonstrations.
January 28 - Iran hangs two men on convictions of being "enemies of God" and plotting to overthrow government.
January 30 - Mir Hossein Mousavi and Mehdi Karroubi call for a public demonstration on February 11, the anniversary of the nation's Islamic revolution.
February 3 - Iranian officials announce that nine demonstrators will be hanged "soon" over post-election unrest.
February 10 - Ali Motahari, one of Iran's most prominent conservative politicians, says that everyone, including opposition groups, should be allowed to rally during the anniversary.
February 11 - Tens of thousands of Iranians take to the streets of Iran to mark the 31st anniversary of the country's Islamic revolution. Heavy security was deployed in the country to prevent opposition protests.
Mehdi Karroubi was attacked on his way to the rally, but wasn't seriously hurt. Mohammed Khatami was also reportedly attacked.
There were also reports that Khomeini's grand-daughter and her husband - who is Khatami's brother - were arrested on the anniversary.