Timeline: Colombia

A chronology of key events:

1525 - Spain begins conquest of Colombia.

1536-38 - Spain establishes the settlement of Santa Fe de Bogota, which subsequently becomes known as Bogota, the current capital; becomes part of the Spanish vice-royalty of Peru.

Skyscrapers, colonial buildings rub shoulders in Bogota Population: 6.4 million Elevation: 2,640 metres above sea level

1718 - Bogota becomes the capital of the Spanish vice-royalty of Nueva Granada, which also rules Ecuador and Venezuela.

1819 - Simon Bolivar defeats Spanish at Boyaca. Republic of Gran Colombia formed with Ecuador, Panama and Venezuela.

1829-30 - Gran Colombia dissolved when Venezuela and Ecuador split off, leaving present-day Colombia and Panama a separate state known as Nueva Granada.

1849 - Conservative and Liberal parties founded.

1861-85 - Liberal Party rule sees country divided into nine largely autonomous entities and the church separated from the state.

Festival time in the northern city of Barranquilla

1885 - Start of 45 years of Conservative Party rule during which power is recentralised and church influence restored.

1899-1903 - "The War of the Thousand Days": around 120,000 people die in civil war between Liberals and Conservatives. Panama becomes an independent state.

1930 - Liberal President Olaya Herrera elected by coalition; social legislation introduced and trade unions encouraged.

1946 - Conservatives return to power.

1948 - Assassination of left-wing mayor of Bogota ignites riots.

1948-57 - 250,000-300,000 killed in civil war.

1958 - Conservatives and Liberals agree to form National Front in a bid to end the civil war; other parties banned.

Guerrilla war

1965 - Leftist National Liberation Army (ELN) and Maoist People's Liberation Army (EPL) founded.

Colombia's main rebel group, the Farc, appears to be losing ground Colombia's most powerful rebels Obituary: Manuel Marulanda Rescue deals Farc a blow

1966 - Revolutionary Armed Forces of Colombia (Farc, the current largest guerrilla grouping) set up.

1970 - National People's Alliance formed as a left-wing counterweight to the National Front.

1971 - Left-wing M-19 guerrilla group emerges.

1978 - President Julio Turbay (Liberal) begins intensive fight against drug traffickers.

1982 - President Belisario Betancur (Conservative) grants guerrillas amnesty and frees political prisoners.

War against drug cartels stepped up

1984 - Campaign against drug traffickers stepped up following assassination of justice minister.

1985 - Eleven judges and 90 other people killed after M-19 guerrillas force their way into the Palace of Justice; Patriotic Union Party (UP) founded.

Nevado del Ruiz volcano erupts. An estimated 23,000 people are killed in four Andean towns.

1986 - Virgilio Barco Vargas (Liberal) wins presidential elections by record margin. Right-wing paramilitary groups begin murder campaign against UP politicians, amid continuing violence by left-wing groups and death squads run by drugs cartels.

1989 - M-19 becomes legal party after reaching peace agreement with government.

Andres Pastrana secured US aid but failed to stem violence 2005: Ex-Colombia leader named US envoy 2002: Pastrana's legacy of failure

1989 - Liberal and UP presidential candidates murdered during presidential election campaign, reputedly at the behest of drug cartels; Cesar Gaviria elected on anti-drug platform.

1991 - New constitution legalises divorce, prohibits extradition of Colombians wanted for trial in other countries and guarantees indigenous peoples' democratic rights, but without addressing their territorial claims.

1993 - Pablo Escobar, Medellin drug-cartel leader, shot dead while trying to evade arrest.

1995 - Ernesto Samper Pizano (Liberal) elected president and is subsequently charged and cleared of receiving drug-cartel money for his election campaign.

Peace talks

1998 - Andres Pastrana Arango - a Conservative - elected president, begins peace talks with guerrillas.

1998 November - Pastrana grants Farc a safe haven the size of Switzerland in the south-east to help move peace talks along. The zone is off-limits to the army.

1999 January - Peace talks formally launched but proceed in stop-start fashion. Pastrana and Farc leader Manuel "Sureshot" Marulanda meet.

1999 January - Powerful earthquake kills some 1,000 people. Cities of Armenia and Pereira badly hit.

Plan Colombia

2000 July - Pastrana's "Plan Colombia" wins almost US$1 billion in mainly military aid from the US to fight drug-trafficking and rebels who profit and protect the trade.

Plan Colombia: US has pumped billions into anti-drugs drive 2006: Colombia's 'lost war' against cocaine 2005: US weighs costs of Plan Colombia

2000 September - Government freezes talks; alleges Farc harboured hijacker of plane forced to land in safe haven. Later, Farc refuses to resume talks, accuses Pastrana of not stopping paramilitary groups.

2001 February - The Farc return to peace talks after meeting between "Sureshot" and Pastrana. Pastrana extends demilitarized area for eight months.

2001 June - Farc rebels free 359 police and troops in exchange for 14 captured rebels. Farc accused of using safe haven to rearm, prepare attacks and conduct drug trade.

2001 October - Government, Farc sign San Francisco agreement, committing themselves to negotiate ceasefire. Pastrana extends life of safe haven until January 2002.

2002 January - Pastrana accepts Farc ceasefire timetable and extends safe haven until April.

Talks fail

2002 20 February - Pastrana breaks off three years of tortuous peace talks with Farc rebels, says hijacking of aircraft hours earlier is final straw. He orders rebels out of demilitarised zone. Government declares war zone in south after rebels step up attacks.

2002 May - Independent candidate Alvaro Uribe wins a first-round presidential election victory, promises to crack down hard on rebel groups.

Demobilisation: AUC fighters hand in weapons AUC called ceasefire in 2002; peace talks began in 2004 Group listed as terrorist organisation in Europe and US Most rank-and-file members will get full pardon and job training 2004: Colombia's 'drug barons' in peace talks

2002 August - Moments before Alvaro Uribe is sworn in as president, suspected Farc explosions rock Bogota. Twenty people are killed. Days later, Uribe declares state of emergency.

2003 October - 14 out of 15 of President Uribe's planned austerity measures and political reforms rejected by voters in referendum. Three ministers, national police chief resign.

2003 November - Fighters from right-wing United Self-Defence Forces of Colombia (AUC) begin to disarm.

2004 May - Farc's Ricardo Palmera, the most senior Colombian guerrilla ever captured, is jailed for 35 years.

2004 July - Right-wing AUC and government begin peace talks. AUC leaders address Congress.

2005 January - Bitter 15-day dispute with Venezuela over the capture of a Farc leader on Venezuelan soil. The affair is resolved at talks in Caracas in February.

2005 June - New law offers reduced jail terms and protection from extradition for paramilitaries who turn in their arms. Rights groups say the legislation is too lenient.

2005 December - Exploratory peace talks with the second biggest left-wing rebel group, the National Liberation Army (ELN), begin in Cuba.

2006 February - Colombia and the US agree on a free trade deal. The agreement awaits ratification in both countries.

Uribe's second term

2006 March - Parties loyal to President Uribe win an overwhelming victory in parliamentary elections.

2006 May - President Uribe wins a second term in office.

2006 November - Court investigates possible ties between high-ranking politicians from Sucre department and right-wing paramilitaries.

2006 December - Detained paramilitary leaders say they are pulling out of a peace process. Government says demobilisation of right-wing groups will continue.

2007 January - Ecuador turns to the Organisation of American States (OAS) for help with its challenge to Colombia's coca crop-spraying programme along their common border.

2007 June - Government releases dozens of jailed Farc guerrillas, in hope that rebels will reciprocate by releasing hostages. Farc rejects move, saying it will only free hostages if government pulls back troops and sets up demilitarised zone.

2007 July - Hundreds of thousands protest in Bogota against kidnappings and conflict in the country.

Hostage release talks

2007 September - In his role as mediator, Venezuelan President Hugo Chavez agrees to invite rebels for talks on hostage release deal.

2007 November - Colombia sets deadline of 31 December for President Chavez to reach deal with rebels on prisoner swap.

2007 November - Venezuelan President Hugo Chavez withdraws his country's ambassador to Bogota in a row over his role in negotiations between the Colombian government and rebel forces.

2008 January - The Farc releases two high-profile hostages, Clara Rojas and Consuelo Gonzalez, as a result of Mr Chavez's mediation.

Mr Chavez calls on the US and European governments to stop treating Colombian left-wing rebel groups as terrorists, but Mr Uribe rejects the idea.

2008 March - A Colombian cross-border strike into Ecuador kills senior Farc rebel Raul Reyes and sparks a diplomatic crisis with both Ecuador and Venezuela.

2008 May - Colombia extradites 14 paramilitary warlords to the United States to stand trial on drug trafficking charges. US hails move as evidence Colombia deserves trade deal. Colombian opposition complains the extraditions mean that the militia leaders will not reveal their alleged links to political allies of Mr Uribe.

Farc announces death of its leader and founder, Manuel Marulanda.

2008 June - Colombia renews low-level diplomatic relations with Ecuador.

Betancourt freed

2008 July - Colombian army rescues the country's highest-profile hostage, Ingrid Betancourt, held in captivity for six years by Farc. She was among 15 hostages freed in an operation in the Guaviare region, close to the Venezuelan border.

In a sign of warming relations, Mr Uribe visits Venezuela for talks with Mr Chavez.