In the 1920s, the Soviet government established the Nagorno-Karabakh Autonomous Region—where 95 percent of the population is ethnically Armenian—within Azerbaijan. Under Bolshevik rule, fighting between the two countries was kept in check, but, as the Soviet Union began to collapse, so did its grip on Armenia and Azerbaijan. In 1988, the Nagorno-Karabakh legislature passed a resolution to join Armenia despite the region's legal location within Azerbaijan’s borders. As the Soviet Union was dissolving in 1991, the autonomous region officially declared independence. War erupted between Armenia and Azerbaijan over the region, leaving roughly thirty thousand casualties and hundreds of thousands of refugees. By 1993, Armenia controlled Nagorno-Karabakh and occupied 20 percent of the surrounding Azerbaijani territory. In 1994, Russia brokered a cease-fire which has remained in place since.
Nagorno-Karabakh has been a frozen conflict for more than a decade, but artillery shelling and minor skirmishes between Armenian and Azerbaijani troops have caused hundreds of deaths. Early April 2016 witnessed the most intense fighting since 1994, killing dozens and resulting in more than three hundred casualties. After four days of fighting, the two sides announced that they had agreed on a new cease-fire. However, a breakdown in talks was followed by repeated cease-fire violations, and tensions have remained high.
Negotiation and mediation efforts, primarily led by the Minsk Group, have failed to produce a permanent solution to the conflict. The Minsk Group, a mediation effort led by the Organization for Security and Cooperation in Europe (OSCE), was created in 1994 to address the dispute and is co-chaired by the United States, France, and Russia. The co-chairs organize summits between the leaders of the two countries and hold individual meetings. The group has successfully negotiated cease-fires, but the territorial issues remain as intractable as ever. In October 2017, the presidents of Armenia and Azerbaijan met in Geneva under the auspices of the Minsk Group, beginning a series of talks on a possible settlement of the conflict. However, talks have yet to produce concrete results.
Because Azerbaijani and ethnic Armenian military forces are positioned close to each other and have little to no communication, there is a high risk that inadvertent military action could lead to an escalation of the conflict. The two sides also have domestic political interests that could cause their respective leaders to launch an attack.
Without successful mediation efforts, cease-fire violations and renewed tensions threaten to reignite a military conflict between the countries and destabilize the South Caucasus region. This could also disrupt oil and gas exports from the region, since Azerbaijan, which produces about eight hundred thousand barrels of oil per day, is a significant oil and gas exporter to Central Asia and Europe. Russia has promised to defend Armenia, Turkey has pledged to support Azerbaijan, and Iran has a large Azeri minority, which could escalate a crisis and further complicate efforts to secure peace in the region.
The risk of military conflict is escalating in Nagorno-Karabakh, the border region claimed by both Armenia and Azerbaijan, due to the failure of mediation efforts, increased militarization, and frequent cease-fire violations. In late September 2020, heavy fighting broke out along the border—the most serious escalation since 2016. More than one thousand soldiers and civilians have been killed, with hundreds more wounded on both sides. Armenia and Azerbaijan initially rejected pressure from the United Nations and countries like the United States and Russia to hold talks and end hostilities, and instead pledged to continue fighting. Tensions escalated further when both sides switched from cross-border shelling to the use of longer-range artillery and other heavy weaponry. In early October 2020, Russia negotiated a cease-fire, which broke down; two additional cease-fires were negotiated by France in coordination with Russia and the United States, and then the United States directly. These cease-fires also collapsed almost immediately as fighting continued with reported violations by both Armenia and Azerbaijan.
These recent hostilities follow a series of cross-border attacks that occurred over the summer, including four days of clashes and shelling in July 2020 that killed an Azerbaijani general and nearly twenty people.