After the provisional government of Ahmet Tevfik Pasha failed to win support for ratification of the treaty, remnants of the Ottoman Army's XV Corps under the command of Kâzım Karabekir attacked Armenian forces controlling the area surrounding Kars, eventually recapturing most of the territory in the South Caucasus that had been part of the Ottoman Empire prior to the Russo-Turkish War (1877–1878) and was subsequently ceded by Soviet Russia as part of the Treaty of Brest-Litovsk.

[15][16][17][18] One estimate places the number of Armenians massacred by the Turkish army during the war at 100,000[18]—this is evident in the marked decline (−25.1%) of the population of modern-day Armenia from 961,677 in 1919[19] to 720,000 in 1920.

The dissolution of the Russian Empire in the wake of the February Revolution saw the Armenians of the South Caucasus declaring their independence and formally establishing the First Republic of Armenia.

[21] In its two years of existence, the republic, with its capital in Yerevan, was beset with a number of debilitating problems, including fierce territorial disputes with its neighbors and a severe refugee crisis.

[23]: 416 During the First World War and in the ensuing peace negotiations in Paris, the Allies had vowed to punish the Turks and reward some, if not all, of the eastern provinces of the empire to the nascent Armenian republic.

In matters related to the Near East, the principal powers, Great Britain, France, Italy and the United States, had conflicting interests over the spheres of influence they were to assume.

[29] In the negotiations of the Treaty of Moscow (1921), the Bolsheviks demanded that the Turks cede Batum and Nakhichevan; they also asked for more rights in the future status of the Straits.

According to historian Richard G. Hovannisian, Kemal's decision to order attacks on Armenian troops in Oltu District in the erstwhile Kars Oblast that eventually expanded into an invasion of Armenia proper was intended to show the Allies that "the treaty would not be accepted and that there would be no peace until the West was ready to offer new terms in keeping with the principles of the Turkish National Pact.

[34] Using Turkish sources, historian Bilâl Şamşir has identified mid-June as to when exactly the Ankara government began to prepare for a campaign in the east.

[38] Skirmishes between Turkish and Armenian forces in the area surrounding Kars were frequent during that summer, although full-scale hostilities did not break out until September.

[40] As neither the Allied powers nor Soviet Russia reacted to Turkish operations, on September 20 Kemal authorized Karabekir to push onwards and take Kars and Kağızman.

At 3:00 in the morning of 28 September, the four divisions of the XV Army Corps advanced towards Sarıkamış, creating such panic that Armenian residents had abandoned the town by the time the Turks entered the next day.

Most of Britain's available forces in the Near East were concentrated on crushing the Kurdish tribal uprisings in Iraq with the help of the Assyrians, while France and Italy were also fighting the Turkish revolutionaries near Syria and Italian controlled Antalya.

[1] On 12 November, the Turks also captured the strategic village of Aghin, northeast of the ruins of the former Armenian capital of Ani, and planned to move toward Yerevan.

It had concluded an agreement with Armenia to invade the disputed region of Lori, which was established as a Neutral Zone (the Shulavera Condominium) between the two nations in early 1919.

On the night of 28–29 November, the Soviet Eleventh Army under the command of Anatoli Gekker invaded Armenia at Karavansarai (present-day Ijevan), meeting little to no resistance.

The Red Army intervened to restore Soviet authority, although anti-Bolshevik resistance continued in the southern region of Zangezur until July 1921.

The warfare in Transcaucasia was settled in a friendship treaty between the Grand National Assembly of Turkey (GNAT) (which proclaimed the Turkish Republic in 1923), and Soviet Russia (RSFSR).