A chronology of key events:
Fifth century BC - Indo-Aryan migrants from northern India settle on the island; the Sinhalese emerge as the most powerful of the various clans.
Third century BC - Beginning of Tamil migration from India.
1505 - Portuguese arrive in Colombo, marking beginning of European interest.
1658 - Dutch force out Portuguese and establish control over whole island except central kingdom of Kandy.
1796 - Britain begins to take over island.
1815 - Kingdom of Kandy conquered. Britain starts bringing in Tamil labourers from southern India to work in tea, coffee and coconut plantations.
1833 - Whole island united under one British administration.
1931 - British grant the right to vote and introduce power sharing with Sinhalese-run cabinet.
1948 - Ceylon gains full independence.
1949 - Indian Tamil plantation workers disenfranchised and many deprived of citizenship.
1956 - Solomon Bandaranaike elected on wave of Sinhalese nationalism. Sinhala made sole official language and other measures introduced to bolster Sinhalese and Buddhist feeling. More than 100 Tamils killed in widespread violence after Tamil parliamentarians protest at new laws.
1958 - Anti-Tamil riots leave more than 200 people dead. Thousands of Tamils displaced.
1959 - Bandaranaike assassinated by a Buddhist monk. Succeeded by widow, Srimavo, who continues nationalisation programme.
1965 - Opposition United National Party wins elections and attempts to reverse nationalisation measures.
1970 - Srimavo Bandaranaike returns to power and extends nationalisation programme.
1971 - Sinhalese Marxist uprising led by students and activists.
1972 - Ceylon changes its name to Sri Lanka and Buddhism given primary place as country's religion, further antagonising Tamil minority.
1976 - Liberation Tigers of Tamil Eelam (LTTE) formed as tensions increase in Tamil-dominated areas of north and east.
1977 - Separatist Tamil United Liberation Front (TULF) party wins all seats in Tamil areas. Anti-Tamil riots leave more than 100 Tamils dead.
1981 - Sinhala policemen accused of burning the Jaffna Public Library, causing further resentment in Tamil community.
1983 - 13 soldiers killed in LTTE ambush, sparking anti-Tamil riots leading to the deaths of several hundred Tamils. Start of what Tigers call "First Eelam War".
Civil war intensifies
1985 - First attempt at peace talks between government and LTTE fails.
1987 - Government forces push LTTE back into northern city of Jaffna. Government signs accords creating new councils for Tamil areas in north and east and reaches agreement with India on deployment of Indian peace-keeping force.
1988 - Left-wing and nationalist Sinhalese JVP begins campaign against Indo-Sri Lankan agreement.
1990 - Indian troops leave after getting bogged down in fighting in north. Violence between Sri Lankan army and separatists escalates. "Second Eelam War" begins.
Thousands of Muslims are expelled from northern areas by the LTTE.
1991 - LTTE implicated in assassination of Indian premier Rajiv Gandhi in southern India.
War and diplomacy
1993 - President Premadasa killed in LTTE bomb attack.
1994 - President Kumaratunga comes to power pledging to end war. Peace talks opened with LTTE.
1995 - "Third Eelam War" begins when rebels sink naval craft.
1995-2001 - War rages across north and east. Tigers bomb Sri Lanka's holiest Buddhist site. President Kumaratunga is wounded in a bomb attack. Suicide attack on the international airport destroys half the Sri Lankan Airlines fleet.
2002 - February - Government and Tamil Tiger rebels sign a Norwegian-mediated ceasefire.
De-commissioning of weapons begins; the road linking the Jaffna peninsula with the rest of Sri Lanka reopens after 12 years; passenger flights to Jaffna resume. Government lifts ban on Tamil Tigers. Rebels drop demand for separate state.
2003 - Tigers pull out of talks. Ceasefire holds.
2003 May - Country's worst-ever floods leave more than 200 people dead and drive some 4,000 people from their homes.
2004 March - Renegade Tamil Tiger commander, known as Karuna, leads split in rebel movement and goes underground with his supporters. Tiger offensive regains control of the east.
2004 July - Suicide bomb blast in Colombo - the first such incident since 2001.
2004 December - More than 30,000 people are killed when a tsunami, massive waves generated by a powerful undersea earthquake, devastate coastal communities.
2005 June - Row over deal reached with Tamil Tiger rebels to share nearly $3bn in tsunami aid among Sinhalas, Tamils and Muslims.
2005 August - State of emergency after foreign minister is killed by a suspected Tiger assassin.
2005 November - Mahinda Rajapaksa, prime minister at the time, wins presidential elections. Most Tamils in areas controlled by the Tamil Tigers do not vote.
2006 April - Attacks begin to escalate again.
A suicide bomber attacks the main military compound in Colombo, killing at least eight people. The military launch air strikes on Tamil Tiger targets.
2006 May - Tamil Tiger rebels attack a naval convoy near Jaffna.
2006 August - Tamil Tiger rebels and government forces resume fighting in the north-east in worst clashes since 2002 ceasefire. Government steadily drives Tamil Tigers out of eastern strongholds over following year.
2006 October - Peace talks fail in Geneva.
2007 June - Police force hundreds of Tamils out of the capital, citing security concerns. A court orders an end to the expulsions.
2008 January - Government pulls out of 2002 ceasefire agreement, launches massive offensive.
2008 March - International panel, invited by the government to monitor investigations into alleged human rights abuses, announces that it is leaving the country. Panel member Sir Nigel Rodley says the authorities were hindering its work. Government rejects the criticism.
2008 July - Sri Lankan military says it has captured the important Tamil Tiger naval base of Vidattaltivu in the north.
2008 October - Suicide bombing blamed by government on Tamil Tigers kills 27 people, including a former general, in the town of Anuradhpura.
2008 December - Sri Lankan troops and Tamil rebels claim to have inflicted heavy casualties on each other in fierce fighting in the north.
2009 January - Government troops capture the northern town of Kilinochchi, held for ten years by the Tamil Tigers as their administrative headquarters. President Mahinda Rajapakse calls it an unparalleled victory and urges the rebels to surrender.
2009 February - International concern over the humanitarian situation of thousands of civilians trapped in the battle zone prompts calls for a temporary cease-fire. This is rejected by the government, which says it is on the verge of destroying the Tamil Tigers, but it offers an amnesty to rebels if they surrender.
Tamil Tiger planes conduct suicide raids against Colombo.
Tamil Tigers defeated
2009 March - Former rebel leader Karuna is sworn in as minister of national integration and reconciliation. United Nations High Commissioner for Human Rights Navi Pillay accuses both sides of war crimes.
The government rejects conditions attached to an IMF emergency loan worth $1.9 billion, denies US pressure causing delay to agreement.
2009 May - Government declares Tamil Tigers defeated after army forces overrun last patch of rebel-held territory in the northeast. Military says rebel leader Velupillai Prabhakaran was killed in the fighting. Tamil Tiger statement says the group will lay down its arms.
2009 August - New Tamil Tiger leader Selvarasa Pathmanathan captured overseas by Sri Lankan authorities.
First post-war local elections in north. Governing coalition wins in Jaffna but in Vavuniya voters back candidates who supported Tamil Tigers.
2009 October - Government announces early presidential and parliamentary elections.
2009 November - Opposition parties form alliance to fight elections. The new alliance includes Muslim and Tamil parties and is led by former prime minister Ranil Wickremesinghe.
Government says 100,000 refugees released from camps.
2009 December - European Union says will suspend Sri Lanka's preferential trade status over alleged human rights concerns.
2010 January - Incumbent Mahinda Rajapaksa wins presidential election by a big margin but the outcome is rejected by his main rival Gen Sarath Fonseka.
2010 February - Gen Fonseka is arrested. The government says he will be court-martialled on conspiracy charges. President Rajapaksa dissolves parliament, clearing way for elections in April.
2010 April - President Rajapaksa's ruling coalition wins landslide victory in parliamentary elections.
2010 August - Military court finds former army chief Sarath Fonseka guilty of involvement in politics while in uniform and sentences him to a dishonourable discharge.
2010 September - Parliament approves a constitutional change allowing President Rajapaksa to seek unlimited number of terms.
2011 April - UN says both sides in the Sri Lankan civil war committed atrocities against civilians and calls for an international investigation into possible war crimes. Sri Lanka says the report is biased.
2011 July - Sri Lanka's largest ethnic Tamil party, the Tamil National Alliance - wins two-thirds of local councils in the former war zone in the north and east.
2011 August - President Rajapaksa says his government will allow the expiry of state emergency laws which have been in place for most of the past 40 years.
Government introduces new legislation allowing the detention of people suspected of terror offences without charge.
2011 September - Parliament approves law allowing government to take over 37 businesses. Critics say they will be seized from opponents to reward supporters.
2012 January - 160 Islamic clerics expelled for violating visa regulations.