Upon the disintegration of the Transcaucasian Federation with the proclamation of the independent Democratic Republic of Georgia on May 26, 1918, both Azerbaijan and Armenia proclaimed their independence on the same day, May 28, 1918. Both Armenia and Azerbaijan laid claim to territory which they saw as historically and ethnically theirs; these territorial disputes led to the Armenian–Azerbaijani War between 1918 and 1920, a series of conflicts that ended only when both Armenia and Azerbaijan were annexed by the Soviet Union.
Soviet period (1922–91)
Upon the establishment of USSR in 1922, Azerbaijan SSR and Armenian SSR became constituent states, initially as a part of Transcaucasian SFSR, and from 1936 as separate entities. The relations between the two nations, including in Nagorno-Karabakh Autonomous Oblast, were generally peaceful and friendly whilst all Soviet entities. Though occasional confrontations did occur, particularly the 1948 and the 1964 public protests in Armenia which resulted in exodus of a large number of Azeris, they remained unknown to a broader public due to strict Soviet censorship.
Karbakh War
In 1988, the Armenians of Karabakh voted to secede and join Armenia. This, along with massacres in Armenia and Azerbaijan resulted in the conflict that became known as the Nagorno-Karabakh War. The violence resulted in de factoArmenian occupation of former NKAO and seven surrounding Azerbaijani regions which was effectively halted when both sides agreed to observe a cease-fire which has been in effect since May 1994. In late 1995, both also agreed to mediation of the OSCE Minsk Group. The Minsk Group is currently co-chaired by the US, France, and Russia and comprises Armenia, Azerbaijan, Turkey, and several Western European nations. During the conflict the Siege of Stepanakert was held by Azerbaijani forces. From late 1991 to May 1992 the city and its Armenian population was a target of a months-long campaign of intentional civilian bombardment and blockade by Azerbaijan. The indiscriminate shelling, sniper shooting and aerial attacks killed or maimed hundreds of civilians and destroyed homes, hospitals and other buildings that were not legitimate military targets, and generally terrorized the civilian population. Azerbaijan blockaded all essential supplies, including water, electricity, food and medicines causing many deaths. Human Rights Watch reported that the main bases used by Azerbaijani armed forces for the bombardment of Stepanakert included the towns of Khojaly and Shusha. During the conflict the Khojaly massacre occurred which was the mass murder of at least 161 ethnic Azerbaijani civilians from the town of Khojaly on 26 February 1992. According to Human Rights Watch, the tragedy struck when "a large column of residents, accompanied by a few dozen retreating fighters, fled the city as it fell to Armenian forces. As they approached the border with Azerbaijan, they came across an Armenian military post and were cruelly fired upon".
After 1994
After the war, relations between Armenia and Azerbaijan remained very tense. In 2008, Azerbaijani president Ilham Aliyev declared that “Nagorno Karabakh will never be independent; the position is backed by international mediators as well; Armenia has to accept the reality” and that “in 1918, Yerevan was granted to the Armenians. It was a great mistake. The khanate of Iravan was the Azeri territory, the Armenians were guests here." The two countries are still technically at war and the Azerbaijani government regularly threatens to retake Nagorno-Karabakh by military force, if mediation of the OSCE Minsk Group does not succeed. Citizens of Armenia, as well as citizens of any other country who are of Armenian descent, are forbidden entry to the Republic of Azerbaijan. If a person's passport shows any evidence of travel to Nagorno-Karabakh, barring a diplomatic passport, they are forbidden from entering the Republic of Azerbaijan. In 2008, in what became known as the 2008 Mardakert Skirmishes, Armenia and Azerbaijan clashed over Nagorno-Karabakh. The fighting between the two sides was brief, with few casualties on either side. June 2010 saw a brief flare up of the conflict, resulting in the deaths of four Armenian soldiers and one Azeri soldier. The clash came a day after peace talks between the Presidents of Armenia and Azerbaijan which were held in Moscow. On August 31, 2010, a border clash killed three Armenians and two Azeris, although the Armenian military claimed up to seven Azeris had been killed in the fighting. Both sides blamed the other for the incident. This preceded another incident on September 4 in which two Azerbaijani soldiers were killed and one Armenian wounded. On June 24, 2011, the two sides met in Kazan, Russia, to negotiate an end to the Nagorno-Karabakh issue, but the talks ended in failure. Following the breakdown of talks, the Azeri President Ilham Aliyev used the June 26 Salvation Day military parade to warn Armenia that Azerbaijan may retake Nagorno-Karabakh by force. On 5 October 2011, border clashes around Nagorno Karabakh left one Armenian soldier and two Azeris dead. Two Armenians were also wounded by sniper fire the same day. Another violent incident occurred on 5 June 2012 when, according to the Azerbaijani side, Armenian troops crossed the border and shot dead five Azerbaijani soldiers before withdrawing. Armenia denied the claim and accused Azerbaijan of crossing the border first. In October 2013, Zakir Hasanov was appointed as Azerbaijani Defence Minister despite controversy.
2016 clashes
After the 2016 Armenian–Azerbaijani clashes, in which an estimated 350 troops and civilians from both sides were killed, Azerbaijan declared a unilateral cease fire.
After 2016
Amidst the COVID-19 pandemic, which both Azerbaijan and Armenia have struggled to contain, there have been new clashes. A total of 11 Azerbaijani soldiers, including high-ranking officers, and four Armenian soldiers have been killed since July 11, 2020.
