The Nagorno-Karabakh conflict was an ethnic and territorial conflict between Armenia and Azerbaijan over the region of Nagorno-Karabakh, inhabited mostly by ethnic Armenians until 2023, and seven surrounding districts, inhabited mostly by Azerbaijanis until their expulsion during the 1990s. The Nagorno-Karabakh region was entirely claimed by and partially controlled by the breakaway Republic of Artsakh, but was recognized internationally as part of Azerbaijan. Azerbaijan gradually re-established control over Nagorno-Karabakh region and the seven surrounding districts.

An ethnic conflict is a conflict between two or more ethnic groups. While the source of the conflict may be political, social, economic or religious, the individuals in conflict must expressly fight for their ethnic group's position within society. This criterion differentiates ethnic conflict from other forms of struggle.