A chronology of key events:
1516 - Spanish navigator Juan Diaz de Solis killed by indigenous people while exploring the Rio de la Plata, his death discouraging further European colonisation for more than 100 years.
1726 - Spanish found Montevideo and take over Uruguay from the Portuguese; many of the indigenous people are killed.
1776 - Uruguay becomes part of the Vice-royalty of La Plata, which has its capital at Buenos Aires.
1808 - Uruguay rebels against the Vice-royalty of La Plata following the overthrow of the Spanish monarchy by Napoleon Bonaparte.
1812-20 - Orientales, or Uruguayans from the eastern side of the River Plata, fight against Argentinian and Brazilian invaders.
Independence and war
1828 - Brazil, Argentina renounce claims to territories which become the Eastern Republic of Uruguay.
1830 - Constitution approved.
1838-65 - Civil war between Blancos, or Whites - the future conservative party - and Colorados, or Reds - the future liberals.
1865-70 - Uruguay joins Argentina and Brazil in war against Paraguay, which is defeated.
1903-15 - Reformist Jose Batlle y Ordonez (Colorado Party) gives women the franchise and establishes a welfare state, disestablishes the church and abolishes the death penalty during two successive terms as president.
1933 - Opposition groups excluded from politics following military coup.
1939-1945 - World War II. Uruguay is neutral for most of the war but later joins the Allies.
1951 - President replaced with nine-member council in accordance with new constitution.
Dictatorship, guerrilla warfare, return to democracy
1962 - Campaign by Tupamaros guerrillas begins and lasts until 1973.
1971 - British ambassador to Uruguay Geoffrey Jackson kidnapped by Tupamaros guerrillas and held for eight months. He is freed shortly after a mass jail break-out by Tupamaros convicts which officials deny was arranged in exchange for Jackson's release.
1972 - Sixteen survivors of a Uruguayan plane which crashes in the Andes stay alive by eating the flesh of passengers who died. The survivors, mainly members of a Uruguayan rugby team, are trapped for 10 weeks.
1973 - Armed forces seize power and promise to encourage foreign investment, but usher in a period of extreme repression during which Uruguay becomes known as "the torture chamber of Latin America" and accumulates the largest number of political prisoners per capita in the world.
1984 - Violent protests against repression and deteriorating economic conditions.
1985 - Army and political leaders agree on return to constitutional government and the release of political prisoners; law grants amnesty to members of the armed forces accused of human rights violations during years of dictatorship; Julio Maria Sanguinetti becomes president.
1989 - Referendum endorses amnesty for human rights abusers; Lacalle Herrera elected president
1994 - Julio Maria Sanguinetti elected president.
1999 - Jorge Batlle elected president.
2000 - Commission begins investigating the fate of 160 people who disappeared during the years of military dictatorship.
2002 April - Uruguay breaks diplomatic ties with Cuba, after Cuba accuses it of being a US lackey for sponsoring a UN resolution which calls on Havana to implement human rights reforms.
2002 May - Emergency measures, including tax increases, are announced by President Batlle in an effort to prevent Argentina's financial crisis from spilling over the border.
2002 August - Government orders banks to close for almost a week to stop mass withdrawal of savings. General strike held in protest at economic crisis.
2003 April - World Bank approves loans worth more than $250m.
2003 December - Voters in referendum reject plans to open up state oil monopoly to foreign investment.
2004 May - Senate rejects a bill that would have legalised abortion.
Shift to the left
2004 November - Left-winger Tabare Vazquez wins presidential elections, marking a dramatic political shift.
2005 March - President Vazquez is sworn in. Within hours he restores ties with Cuba, signs an energy deal with Venezuela and announces a welfare package to tackle poverty.
2005 December - Forensic experts unearth remains of individuals who are thought to be victims of military rule. President Vazquez ordered the excavations soon after taking office.
2006 July - International Court of Justice rejects a bid by Argentina to suspend the construction of two Uruguayan pulp mills. Uruguay rejects charges that the plants will pollute the border region.
2006 November - Former president-turned-dictator Juan Maria Bordaberry and his former foreign minister are arrested in connection with the 1976 killings of four political opponents.
2006 December - Uruguay pays off its billion-dollar debt to the International Monetary Fund.
2007 May - A new parliament of South America's leading trading block Mercosur is inaugurated in the capital Montevideo.
2007 September - Hundreds of Argentineans cross into Uruguay to protest outside a paper pulp mill, which Argentina and environmentalists say pollutes rivers.
2008 June - President Vasquez announces discovery of what could be large natural gas field off Uruguay's Atlantic coast.
Former dictators jailed
2009 October - The Supreme Court rules that a law shielding officials of the last military government from prosecution for human rights abuses is unconstitutional.
Former military ruler Gregorio Alvarez is sentenced to 25 years in prison for murder and human rights violations.
Ruling Broad Front coalition wins parliamentary election.
2009 November - Former leftist rebel-turned-moderate Jose Mujica of the governing Broad Front wins presidential election.
2010 February - Former president Juan Maria Bordaberry is sentenced to 30 years in prison for murder and violation of the constitution in the wake of the 1973 military coup. Because of his age he serves the sentence at home, and dies in 2011.
2010 March - Jose Mujica takes office as president.
2011 October - Congress votes to revoke an amnesty law that protected military officers from prosecution for crimes committed under military rule in 1975-1983.
2012 October - Uruguay becomes the first country in Latin America after Cuba to legalise abortion for all women. The Senate voted narrowly to allow abortions in the first 12 weeks of pregnancy.
2013 April - Uruguay legalises same-sex marriage, becoming only the second country in Latin America to do so. Argentina, which legalised gay marriage in 2010, was the first.
2013 December - Uruguay becomes the first country to legalise the cultivation, sale and consumption of marijuana for recreational use, as a measure to counter drug cartels. The UN drugs watchdog says the move violates international law.
2014 March - The entire board of Uruguay's Football Association resigns amid a crisis over violence at matches.
2014 November - Tabare Vazquez wins the presidency.
2018 July - Uruguay becomes the first country in the world to legally produce and sell marijuana for recreational use.