Second Nagorno-Karabakh War: Azerbaijan launches an offensive against the self-proclaimed Republic of Artsakh in the Nagorno-Karabakh region, inhabited predominantly by ethnic Armenians.

The Second Nagorno-Karabakh War was an armed conflict in 2020 that took place in the disputed region of Nagorno-Karabakh and the surrounding occupied territories. It was a major escalation of an unresolved conflict over the region, involving Azerbaijan, Armenia and the self-declared Armenian breakaway state of Artsakh. The war lasted for 44 days and resulted in Azerbaijani victory, with the defeat igniting anti-government protests in Armenia. Post-war skirmishes continued in the region, including substantial clashes in 2022.

Azerbaijan, officially the Republic of Azerbaijan, is a transcontinental and landlocked country at the boundary of West Asia and Eastern Europe. It is a part of the South Caucasus region and is bounded by the Caspian Sea to the east, Russia's republic of Dagestan to the north, Georgia to the northwest, Armenia and Turkey to the west, and Iran to the south. Baku is the capital and largest city.

Artsakh, officially the Republic of Artsakh or the Republic of Nagorno-Karabakh, was a breakaway state in the South Caucasus whose territory was internationally recognised as part of Azerbaijan. Between 1991 and 2023, Artsakh controlled parts of the former Nagorno-Karabakh Autonomous Oblast of the Azerbaijani Soviet Socialist Republic, including its capital Stepanakert. It had been an enclave within Azerbaijan from the 2020 Nagorno-Karabakh war until the 2023 Azerbaijani offensive, when the Azerbaijani military took control over the remaining territory controlled by Artsakh. Its only overland access route to Armenia after the 2020 war was via the five-kilometre-wide (3.1 mi) Lachin corridor, which was placed under the supervision of Russian peacekeeping forces.

Nagorno-Karabakh is a region in Azerbaijan, covering the southeastern stretch of the Lesser Caucasus mountain range. Part of the greater region of Karabakh, it spans the area between Lower Karabakh and Syunik. Its terrain mostly consists of mountains and forestland.