Armenian–Azerbaijani War (1918–1920)

Armenian–Azerbaijani War (1918–1920)
Conflict	Armenian–Azerbaijani War (1918–1920)
Date	1918–1920
Place	Caucasus, Nagorno-Karabakh, Nakhchivan, Zangezur, Baku
Result	Sovietization of the First Republic of Armenia and the Azerbaijan Democratic Republic; territorial adjustments under Russian Soviet Federative Socialist Republic and Treaty of Moscow
Combatant1	First Republic of Armenia; Armenian militias; Armenian Revolutionary Federation
Combatant2	Azerbaijan Democratic Republic; Azerbaijani irregulars; Ottoman units; later Denikin's Volunteer Army (indirect)
Commander1	Aram Manukian; Andranik Ozanian; Arshak Jamalyan
Commander2	Fatali Khan Khoyski; Nuri Pasha; Khalil bey Khasmammadov
Casualties	Estimates vary; tens of thousands killed; large civilian displacement

Armenian–Azerbaijani War (1918–1920) was a series of armed conflicts between the First Republic of Armenia and the Azerbaijan Democratic Republic over control of ethnically mixed territories in the southern Caucasus after the collapse of the Russian Empire. The fighting encompassed the regions of Karabakh, Nakhchivan, Zangezur and the oil city of Baku, drawing in local militias, remnants of the Ottoman Empire, and later Soviet forces. The conflict overlapped with the Russian Civil War and the diplomatic activity of the Allied Powers, shaping borders that persisted into the Soviet Union era.

Background

Between 1917 and 1918 the fall of the Russian Empire and the advance of the Ottoman Empire created power vacuums in the South Caucasus that prompted the proclamation of the First Republic of Armenia and the Azerbaijan Democratic Republic. Disputed claims over the multiethnic regions of Nagorno-Karabakh, Nakhchivan, and Zangezur intersected with competing policies of the Transcaucasian Democratic Federative Republic and interventions by the Ottoman Third Army and the British Mission to the Caucasus. Demographic shifts from the Armenian Genocide in Ottoman Empire territories and the collapse of Imperial Russian administration intensified local rivalries among Armenian, Azerbaijani, and Tatar communities, while political parties such as the Armenian Revolutionary Federation and the Musavat Party mobilized for control.

Course of the War

Fighting began in 1918 with local clashes and escalated through 1919–1920 into organized campaigns involving the Armenian National Council and the Azerbaijani provisional authorities, punctuated by sieges and urban violence in Baku and rural confrontations in Zangezur and Karabakh. The entry of the Ottoman Islamic Army of the Caucasus under Nuri Pasha and the subsequent arrival of British forces in Baku altered local balances, while the White movement under Anton Denikin and the advancing Red Army shifted strategic choices for both Yerevan and Baku. By late 1920, Sovietization of the Azerbaijan SSR and the Armenian Soviet Socialist Republic led to ceasefires and imposition of boundaries mediated by the Russian Soviet Federative Socialist Republic.

Major Battles and Campaigns

The Battle of Baku (1918) was a focal event involving the Centrocaspian Dictatorship, Ottoman-backed forces, and Armenian defenders, with implications for oil-rich Baku Oilfields. Campaigns in Karabakh included clashes around Shusha and the mountainous passes linking Goris and Stepanakert, where commanders such as Andranik Ozanian led irregular operations. The Zangezur campaign featured protracted fighting between Armenian units and Azerbaijani irregulars, affecting routes between Nakhichevan and Ordubad. Skirmishes around Nakhchivan and engagements near Yerevan reflected shifting front lines as the Red Army intervened; notable confrontations involved local militia sieges and counterattacks rather than large conventional battles.

Political and Diplomatic Developments

Diplomacy during 1918–1920 involved the Paris Peace Conference, the Allied Powers, and bilateral negotiations between Armenian and Azerbaijani representatives, with mapping efforts by the Caucasus Commission and arbitrations proposed by British Military Mission in Transcaucasia. The Treaty of Batum and subsequent accords attempted to formalize borders but were undermined by military realities and the Treaty of Brest-Litovsk aftermath. Soviet foreign policy, expressed through the People's Commissariat for Foreign Affairs and directives from Vladimir Lenin and Felix Dzerzhinsky, culminated in the recognition of Azerbaijan SSR and the imposition of settlements later adjusted by the Treaty of Moscow (1921) and the Treaty of Kars involving Mustafa Kemal Atatürk's Turkey.

Humanitarian Impact and Ethnic Violence

The war produced widespread civilian suffering, population displacements, and interethnic massacres affecting Armenian, Azerbaijani, and Assyrian communities, exacerbated by sieges of towns like Shusha and episodes in Baku such as the March Days (1918). Refugee flows reached Tiflis and Yerevan, while famine and disease spread in war-affected regions; relief efforts included initiatives by International Committee of the Red Cross delegates and humanitarian missions from the Allied Powers. Estimates of civilian deaths and expulsions vary among contemporaneous reports from the League of Nations observers and later historical scholarship, with contested narratives persisting in Armenian and Azerbaijani historiographies.

Aftermath and Territorial Settlements

By 1921, Sovietization and treaties between the Russian SFSR, Turkey and the Caucasian republics established borders that left Nagorno-Karabakh within the Azerbaijan SSR with autonomous arrangements contested in later decades, while Nakhchivan became an autonomous territory linked to Azerbaijan under the Treaty of Moscow (1921) and the Treaty of Kars. The incorporation of the First Republic of Armenia and the Azerbaijan Democratic Republic into the Soviet Union ended large-scale conventional warfare but institutionalized territorial disparities that contributed to renewed conflicts in the late 20th century such as the Nagorno-Karabakh conflict (1988–1994). Memory politics around the 1918–1920 events remain central to contemporary Armenian and Azerbaijani national discourses.

Category:Caucasus conflicts Category:Wars involving Armenia Category:Wars involving Azerbaijan Category:1918 in Armenia Category:1919 in Azerbaijan Category:1920 in the Soviet Union