Under international law, Nagorno-Karabakh is recognised as part of Azerbaijan. But the ethnic Armenians who make up the vast majority of the population reject Azeri rule. They have been running their own affairs, with support from Armenia, since Azerbaijan's troops were pushed out in a war in the 1990s.
Long-standing ethnic tensions in the region between Christian Armenians and their mainly Muslim neighbours flared in Nagorno-Karabakh in the late 1980s. As the Soviet Union began to break up, it became apparent that Nagorno-Karabakh would come under the direct rule of the Azeri government. The ethnic Armenians did not accept that.
Sectarian conflict erupted, escalating into war in 1991 between Azerbaijan's troops and Nagorno-Karabakh's ethnic Armenian forces backed by Armenia. Thousands of people were killed and hundreds of thousands were displaced.
By 1994, when an internationally brokered ceasefire was agreed, ethnic Armenians controlled almost all of Nagorno-Karabakh, plus some surrounding Azeri districts that gave them a buffer zone and land bridge connecting their region to Armenia. International efforts over the years to find a lasting peace settlement, involving France, the United States and Russia as mediators, have failed to clinch a deal.
It’s feared a conflict could drag in the big regional powers, Russia and Turkey. Moscow has a defence alliance with Armenia, while Ankara backs its ethnic Turkic kin in Azerbaijan.
