1923 - Nagorno-Karabakh Autonomous Region, a largely ethnic Armenian area, established within Azerbaijani Soviet Socialist Republic

1988

Feb - Armenian deputies to National Council of Nagorno-Karabakh vote for unification with Armenia

Two Azerbaijani men killed during a confrontation between Azerbaijanis and Karabakh Armenians near the regional capital. This sparks a pogrom against Armenians in Sumgait city, killing around 30. Attacks on Azerbaijanis in Armenia lead to deaths of more than 200. Both sides dispute the number killed

1988-9 - Hundreds of thousands of ethnic Armenians and ethnic Azerbaijanis leave their homes and seek refuge in their ancestral countries

1990

Jan - Mobs led by hardline Azerbaijani nationalists harass and beat up ethnic Armenians in Baku in an attempt to drive out the city's remaining Armenian population. Moscow sends tanks and troops to secure the area. Around 130 civilians are killed

1991

Jun-Nov - Azerbaijani troops, backed by the Soviet Army, round up thousands of ethnic Armenians who had lived near the Nagorno-Karabakh Autonomous Region. They are deported to Armenia

Following a referendum, Armenia breaks away from Soviet Union. Nagorno-Karabakh declares it is an independent republic. Azerbaijan's Supreme Soviet revokes Nagorno-Karabakh's autonomous status. The region responds by voting in favour of secession

1992

Jan-Mar - Conflict breaks out following dissolution of Soviet Union. Karabakh Armenian troops kill most of Azerbaijani population of the Nagorno-Karabakh village of Khojali, forcing resignation of Azerbaijan's President Ayaz Mutalibov. He is later replaced by President Abulfaz Elchibey

1992

Jun - The Conference for Cooperation and Security in Europe (CCSE) creates 11-country Minsk Group to find a solution

1993

Jun-Oct - A crushing defeat at the hands of the Karabakh Armenians leads to military coup in Azerbaijan. President Abulfaz Elchibey goes into exile. Heydar Aliev returns to power

Karabakh Armenian forces capture four more Azerbaijani districts. With the help of Russian mediation, all sides sign temporary ceasefire agreement in September. Azerbaijan violates ceasefire the following month. Karabakh Armenians retaliate, capturing more territory

1994

May-Dec - Unofficial ceasefire declared following talks in Bishkek, Kyrgyzstan. Meeting between Azerbaijani, Nagorno-Karabakh and Armenian representatives held in Moscow in August to discuss peace settlement

Third round of talks held in Dec. Azerbaijan insists Karabakh Azerbaijanis are included in talks, and asks for process to be mediated by CCSE, later known as the Organisation for Security and Cooperation in Europe (OSCE)

1995

Jun - Talks in Moscow end after Armenia rejects demands from Azerbaijan

1996

Mar - Talks in Moscow fizzle out after little progress is made

1997

Jun-Nov - OSCE presents a series of settlement proposals, which are all rejected

1998

Nov - Minsk Group proposes a "common state" proposal, but this is rejected by Armenia and Azerbaijan

1999

Oct - Presidents Aliyev and Kocharyan meet in a border area and discuss reviving an old U.S. plan that involves a territory swap, sparking controversy in both countries. On Oct. 27, gunmen storm Armenian Assembly and kill several high-ranking politicians, including Prime Minister Vazgen Sargsian

2000

Mar - Nagorno-Karabakh's separatist president, Arkady Gukasyan, seriously wounded in assassination attempt

2001

Jul - Breakdown of peace talks chaired by Minsk Group in Key West, Florida

2002

Mar - United States resumes aid to Azerbaijan as reward for its support in the so-called "war on terror"

2004

Jan - Azerbaijan's President Ilham Aliyev, son of Heidar, announces he will never accept the independence of Nagorno-Karabakh or its integration into Armenia

Jul - OSCE's Minsk Group announces it will not present any further proposals to the two sides

Sep - Tensions rise after Azerbaijan and Armenia accuse each other of violating ceasefire agreement

2005

Jan - Council of Europe passes resolution criticising Armenia's occupation of Azerbaijani territory

Feb - OSCE officials make their first inspection of Azerbaijan territory now under the control of Karabakh Armenia

Mar-Aug - Armenian and Azerbaijani Presidents Robert Kocharyan and Ilham Aliyev meet for talks twice

2006

Jan-Feb - Foreign ministers of Armenia and Azerbaijan outline principles for future action in preparation for summit in France. But talks between Kocharyan and Aliyev fail

Jun - Armenian-Azerbaijani summit in Bucharest fails to produce an agreement

2007

Jan - International mediators visit the region for talks in Baku, Yerevan and Stepanakert and release a cautiously upbeat statement

May - Armenian parliamentary elections

Jul - Bako Saakyan, former security chief, wins election for new leader of Nagorno-Karabakh. Saakyan replaces Gukasyan who stepped down after holding the post for two five-year terms

2008

Feb - Armenian Prime Minister Serzh Sarksyan, an ally of Kocharyan, wins the presidential elections, beating former President Levon Ter-Petrosyan

Mar - Thousands protest over election results, which the opposition says was rigged. The government declares state of emergency and arrests opposition activists

Oct - Ilham Aliyev wins second term as president of Azerbaijan after disputed electoral victory

Nov - Sarksyan and Aliyev sign declaration in Russia to intensify efforts to resolve their dispute over Nagorno-Karabakh. The declaration, however, does not mention status of Nagorno-Karabakh - the main sticking point - and gives no details on how the conflict will be resolved

2009

May - Azerbaijan and Armenia say they have made significant progress in peace talks