A chronology of key events:
1916-18 - Romania fights on Allied side during World War I. As part of the peace settlement at the end of the war acquires several territories with resident Romanian populations - virtually doubling in size and population.
1930s - Rise of fascist "Iron Guard" mass movement.
1938 - King Carol II establishes dictatorship.
1940 - Romania cedes territory to Hungary and USSR after signing of German-Soviet pact. General Ion Antonescu forces King Carol to abdicate in favour of son Michael, but assumes power himself.
1941 - Romania fights on German side against Soviet Union.
1944 - Antonescu ousted. Romania switches sides as Soviet forces close in.
1945 - Soviet-backed government installed.
1947 - Romania regains Transylvania under peace treaty but loses part of Moldavia to the Soviet Union. King Michael abdicates. Romanian People's Republic proclaimed.
1948-49 - Soviet-style constitution, purges of dissidents in the Communist Party.
1952 - Party leader Gheorghe Gheorghiu-Dej becomes prime minister.
1955 - Romania joins Warsaw Pact.
1965 - Nicolae Ceausescu becomes Communist Party leader after death of Gheorghe Gheorghiu-Dej. He pursues foreign policy that runs "independent" of that of Moscow.
1968 - Ceausescu denounces Soviet invasion of Czechoslovakia.
1975 - United States grants Romania most-favoured-nation status.
1977 - Bucharest earthquake kills around 1,500 people.
1985-86 - Austerity programme leads to food shortages and widespread power cuts.
1987 - Army occupies power plants and crushes workers' demonstrations in Brasov.
1989 December - Demonstrations in city of Timisoara against the harassment of a dissident ethnic-Hungarian priest, Laszlo Tokes, trigger bloody national uprising.
Ceausescu and his wife Elena try to flee but are caught and then executed on Christmas Day.
National Salvation Front established, headed by Ion Iliescu.
1990 - Elections confirm Iliescu as head of state. New government of Prime Minister Petre Roman embarks on reform programme.
Securitate secret police replaced by new Romanian Intelligence Service.
Student and opposition protests against the ex-communist leadership are crushed when 20,000 coal miners are brought in to stage a counter demonstration.
1991 - Riots by miners on strike over soaring prices force Roman's resignation. He is replaced by Theodor Stolojan, who sees through a new constitution.
Rise in attacks against Roma minority.
1992 - NSF splits. Iliescu re-elected president. Nicolae Vacaroiu appointed prime minister of minority coalition government.
1994 - Members of ultra-nationalist Romanian National Unity Party appointed to government posts.
1996 - Centre-right election victory sweeps aside former communists. Emil Constantinescu elected president, Victor Ciorbea becomes prime minister.
1997 - Economic reform programme announced. Securitate files opened.
1998 - Ciorbea replaced by Radu Vasile after coalition tensions.
1999 January - Security forces prevent 10,000 miners striking over pay from entering Bucharest.
1999 December - Vasile replaced as prime minister by Mugur Isarescu.
2000 January - Toxic cyanide escapes from mining works in northern Romania and poisons rivers in Hungary and Yugoslavia.
2000 November-December - Ion Iliescu defeats far-right rival Corneliu Vadim Tudor to retake presidency. Leftist Adrian Nastase becomes prime minister in minority government.
2001 January - Parliament approves a law aimed at returning to its original owners property nationalised during the Communist era.
2002 November - Romania formally invited to join Nato at Prague summit.
Path to EU membership
2003 October - Romanians vote in a referendum on a new constitution meant to bring their country into line with members of the European Union.
2004 March - Romania admitted to Nato.
2004 October - President Iliescu ends decades of denial by admitting Romanian complicity in Nazi-driven Holocaust of World War II when hundreds of thousands of Jews and Romanies were sent to their deaths by the country's fascist leadership.
2004 November-December - Centrist alliance leader Traian Basescu elected president. His ally Calin Tariceanu becomes prime minister. Both pledge to speed up EU-oriented reforms.
2005 April - Romania signs EU accession treaty, putting it on course to join in 2007 provided reforms are implemented in time.
2005 July - New leu currency introduced as four zeroes are stripped from old leu as part of preparations for planned EU entry.
2005 December - US Secretary of State Condoleeza Rice visits, signs agreement which will allow US to use Romanian military bases.
2006 December - Official report says up to two million people were killed or persecuted by Romania's former communist authorities.
2007 January - Romania and Bulgaria join the European Union, raising the EU membership to 27.
2007 May - President Basescu survives a parliamentary bid to impeach him when he wins the backing of voters in a referendum.
2007 October - EU threatens to withhold farm aid if Romania does not reform its agricultural payments system.
2008 February - European Commission warns Romania over high-level corruption, pointing to slow pace of investigations into activities of eight serving or former ministers. It gives the country six months to correct serious failings or face sanctions.
2008 December - Democratic Liberal Party President and Mayor of Cluj-Napoca Emil Boc forms coalition government, following inconclusive general elections in November.
2009 March - The International Monetary Fund and other lenders agree to provide Romania a rescue package worth 20bn euros.
2009 April - Romania condemns new measures brought against Romanian nationals in neighbouring Moldova following violent protests in Chisinau. Moldova accuses Romania of fomenting the unrest.
2009 October - Social Democrat Party pulls out of ruling coalition, leaving Prime Minister Emil Boc at head of minority government, which subsequently loses a confidence vote in parliament.
2009 December - Incumbent President Traian Basescu declared winner of run-off election by very narrow majority. Emil Boc forms new coalition government.
2010 February - Romanian Defence Council agrees to host missile interceptors as part of new US defence shield, subject to parliamentary approval.
2010 May - Government announces package of austerity measures that includes large-scale cuts to public sector wages and pensions. Tens of thousands of public sector workers in Bucharest protest against the plans.
2010 July - Implementation of sweeping austerity measures - including 25% cuts to public sector wages - leads to wave of strikes and protests.
2010 September - EU calls on Romania to take urgent action to tackle crime and corruption.
2010 December - France and Germany block Romania from joining Schengen passport-free zone, saying it still needs to make "irreversible progress" in fight against corruption and organised crime.
2011 June - The Netherlands delays until next year any decision on whether to let Bulgaria and Romania join Europe's passport-free Schengen zone, despite a European Parliament vote to let the two countries into Schengen.
2012 January-February - Protests against austerity measures and corruption lead to clashes with police and prompt the resignation of Prime Minister Emil Boc. Foreign Intelligence Service Chief Mihai-Razvan Ungureanu takes over as head of the same coalition.
2012 April - Mr Ungureanu loses a vote of confidence over the austerity programme. President Basescu asks opposition centre-left Social Democratic Party leader Victor Ponta to form a government.