Here is a timeline of major events in the Arab Spring in the last year.
January 14, 2011 - After days of clashes in Tunisia in which dozens are killed, and having made empty promises of reforms and elections, President Zine al-Abidine Ben Ali flees to Saudi Arabia.
January 25 - Anti-government protests begin across Egypt.
January 28 - Egyptian President Hosni Mubarak orders troops and tanks into cities to quell demonstrations. Thousands cheer at news of intervention of the army, widely seen as a neutral force in politics.
January 29 - Yemen's ruling party calls for dialogue with the opposition. Supporters of President Ali Abdullah Saleh attack Yemenis trying to march in solidarity with Egyptian anti-government demonstrators.
February 3 - A day of anti-government protests brings more than 20,000 people onto the streets in Yemen's capital Sanaa.
February 11 - Mubarak steps down and a military council is formed to run the country's affairs.
February 14 - Anti-government "Day of Rage" in the Gulf state of Bahrain, inspired by popular upheavals in Egypt and Tunisia.
February 15/16 - The arrest of human rights activist Fethi Tarbel starts a riot in the Libyan city of Benghazi.
February 24 - Anti-government militias take control of central coastal city of Misrata after evicting forces loyal to Libyan leader Muammar Gaddafi.
March 5 - The rebel National Transitional Council in Benghazi declares itself Libya's sole representative.
March 15 - Bahrain declares martial law.
March 16 - Bahraini forces crack down on protesters, clearing hundreds from the camp that had become their symbol.
March 16 - Security forces break up gathering in a square in Syria's capital, Damascus, of 150 protesters holding pictures of imprisoned relatives.
March 17 - The U.N. Security Council votes to authorise a no-fly zone over Libya and military action to protect civilians against Gaddafi's army.
March 18 - Snipers kill 52 protesters at Sanaa University. Saleh declares a state of emergency.
March 19 - The first air strikes halt the advance of Gaddafi's forces on Benghazi and target Libya's air defences.
April 19 - Syrian government passes bill lifting emergency rule.
June 3 - A bomb explodes at Saleh's palace in Sanaa, wounding the president, the prime minister and the parliament speaker. Saleh leaves for treatment in Riyadh.
June 20 - A Tunisian court sentences Ben Ali and his wife Leila Trabelsi, in absentia, to 35 years in jail for theft and for illegally possessing large sums of cash.
July 31 - Syrian tanks storm the city of Hama, residents say, after besieging it for nearly a month. At least 80 people are killed.
August 3 - Mubarak trial opens. Wheeled into a courtroom cage on a bed, Mubarak denies charges of killing protesters and abuse of power.
August 21 - Rebels enter Libya's capital, Tripoli, with little resistance. Gaddafi makes audio addresses over state television calling on Libyans to fight off the rebel "rats".
September 23 - Saleh returns from Saudi Arabia, greeted by gunfire and explosions.
October 20 - Gaddafi is captured and killed as NTC fighters take his hometown Sirte, ending a two-month siege.
October 23 - Libya declares the liberation of the nation.
-- In Tunisia, the Islamist Ennahda party wins 90 seats in the 217-seat constituent assembly in the country's first democratic election.
November 12 - Arab League suspends Syria.
November 18. - Thousands of people, frustrated with military rule, protest in Cairo's Tahrir Square and in other cities.
November 22 - Egyptian military leader Hussein Tantawi promises that a civilian president will be elected in June 2012, six months sooner than the army had planned.
November 23 - Saleh signs a deal brokered by Gulf states in Saudi Arabia. Saleh is to hand over to his deputy, Abd-Rabbu Mansour Hadi. New presidential elections set for February 2012.
-- An inquiry panel investigating abuses says Bahrain's security forces used excessive force to suppress pro-democracy protests earlier in the year, torturing detainees to get confessions.
November 28 - First round of voting in elections for Egypt's lower house. The staggered election runs through January.
December 13 - U.N. High Commissioner for Human Rights Navi Pillay reports death toll from nine months of unrest in Syria has risen to more than 5,000.
January 10 - Syria's president Bashar al-Assad, in a televised speech at Damascus university, says he will not stand down and vows to strike "terrorists" with an iron fist.
January 14 - Tunisia holds celebrations in the capital to mark one year from the ousting of its autocratic leader.
(Reporting by David Cutler, London Editorial Reference Unit)