{ { Infobox military conflict
| conflict = Battle of Baku 1918
| partof = the Armenian–Azerbaijani War in the Caucasus Campaign of World War I & Southern Front of the Russian Civil War | image = Baku az vs.jpg | image_size = 300px | caption = Ottoman artillery bombarding the city. | place = Baku, Azerbaijan | coordinates = | date = 26 August 1918 – 14 September 1918 | result = Ottoman-Azerbaijani victory | combatant1 = Azerbaijan | combatant2 = Until 26 July: Baku CommuneFrom 26 July: Centrocaspian Dictatorship Armenian Revolutionary Federation White Russians | commander1 = Enver Pasha Nuri Pasha Mursel Bey Ali-Agha Shikhlinski | commander2 = Until 26 July: Stepan Shaumian Grigory Korganov From 26 July: Georgy Dokuchaev Yakov Bagratuni Lionel Dunsterville | strength1 = Islamic Army of the Caucasus14,000 infantry500 cavalry40 guns | strength2 = Baku Army120,000 infantry.40 guns Dunsterforce1,000 infantry1 artillery battery3 machine gun section3 armored cars2 Martinsyde G.100 planes Bicherakhov detachment6,000| casualties1 = 2,000 | casualties2 = Baku Army: 5,000 British Empire: 200 | campaignbox =
}}
The Battle of Baku (, , ) was a battle in World War I that took place between August–September 1918 between the Ottoman–Azerbaijani coalition forces led by Nuri Pasha and Bolshevik–ARF Baku Soviet forces, later succeeded by the British–Armenian–White Russian forces led by Lionel Dunsterville and saw Soviet Russia briefly re-enter the war. The battle was fought as a conclusive part of the Caucasus Campaign, but as a beginning of the Armenian–Azerbaijani War.Dadyan, Khatchatur(2006) Armenians and Baku, p. 118
Background
In 1917, the Russian Caucasus Front collapsed following the abdication of the Tsar. On 9 March 1917, the Special Transcaucasian Committee was established to fill the administrative gap in areas occupied in the course of the war on the Caucasian front by the Russian Provisional Government in the Transcaucasia. This administration, which included representatives of Armenian, Azerbaijani and Georgian groups, did not last long. In November 1917, the first government of the independent Transcaucasia was created in Tbilisi and named the Transcaucasian Commissariat following the Bolshevik seizure of power in St. Petersburg. On 5 December 1917, this new "Transcaucasian Committee" endorsed the Armistice of Erzincan which was signed by the Russians with the command of the Ottoman Third Army. Russian soldiers mainly left the front and returned to their homes. A number of Russian troops left for the Persian Campaign, contrary to the rules of the Armistice. General Nikolai Baratov remained in Hamadan and at Kermanshah, a Russian colonel named Lazar Bicherakhov remained with 10,000 troops. Both forces were supplemented by British liaison officers.
In 1918, the British invited the Armenians to hold out and picked officers and non-commissioned officers to form an "advisory" force, organizing them under the command of Lionel Dunsterville at Baghdad. It was named the Dunsterforce. The military goal of Dunsterforce was to reach the Caucasus via Persia while the Persian Campaign was active. The British planned to organize an army to be recruited from the Armenians and other pro-Allied elements that still existed in the Caucasus. On 10 February 1918, the Sejm gathered and made the decision to establish independence. On 24 February 1918, the Sejm proclaimed Transcaucasia independent as the Transcaucasian Democratic Federative Republic. The Transcaucasian Commissariat was anti-Bolshevik in its political goals and sought the separation of Transcaucasia from Bolshevik Russia. On 27 January 1918, the British mission Dunsterforce set out from Baghdad with officers and instructors to the region. Dunsterforce was ordered to keep the Caucasus-Tabriz front intact and put a stop to Enver Pasha's plans. On 17 February, Dunsterforce arrived at Enzeli; here they were denied passage to Baku by local Bolsheviks, who cited the change in the political situation.
On 3 March 1918, the Grand Vizier Talat Pasha signed the Treaty of Brest-Litovsk with the Russian SFSR. The Treaty of Brest-Litovsk stipulated that the border be pulled back to prewar levels and that the cities of Batum, Kars, and Ardahan be transferred to the Ottoman Empire. Between 14 March – April 1918, the Trabzon peace conference was held between the Ottoman Empire and the delegation of the Sejm.