A conference was held in Kars from September 26 to October 13, 1921, to clarify the relations between Turkey and the South Caucasus republics, including territorial and border issues. By the decision of the Political Bureau of the Central Committee of the Communist Party of Azerbaijan dated August 26, 1921, Behboud Shahtahtinsky, People's Commissar of Justice and the Workers' and Peasants' Inspectorate of the Azerbaijan SSR was appointed the representative of the Azerbaijan SSR at the conference. The Azerbaijani government aimed for strong representation in Kars, highlighted by Behbud Shahtahtinsky's participation in the meeting, indicating the leadership of Soviet Azerbaijan placed great importance on this issue. Nevertheless, in June 1921, S. Danielyan, L. Mirzoyan, and A. Mikoyan, who held leadership positions in the Communist Party of Azerbaijan, along with S. Ordzhonikidze, sought to oust B. Shahtahtinsky from the negotiations and replace him with someone more aligned with their interests. Nonetheless, due to N. Narimanov's steadfast stance on this matter, B. Shahtahtinsky could pursue his work. It's important to mention that the Council of People's Commissars of the Nakhchivan SSR also missioned Taghi Safiyev to advocate for Nakhchivan's interests at the Kars conference.

The Kars conference was marked by tense and principled negotiations, with parties presenting numerous considerations and proposals. Turkey sought to establish separate agreements with each republic. However, Y. Ganetsky, the head of the Russian delegation, prevented this, as directed by the leadership of the RSFSR. On October 13, 1921, the Treaty of Kars was signed between Turkey and the three South Caucasus republics with the participation of a representative from Soviet Russia. Several provisions of the treaty which comprised 20 articles and 3 annexes, were identical to the corresponding articles of the Treaty of Moscow. This document rejected unequal treaties, coerced agreements, and the Treaty of Sèvres. The treaty encompassed a comprehensive range of provisions addressing the territorial matters concerning Kars and Batum, including issues related to the operation of transport communications, the free movement of citizens, and the protection of civil rights, irrespective of nationality or religion. A considerable part focused on addressing the refugee issue and outlining the key areas for developing economic, cultural, and consular relations between the parties involved.

The fifth article of the treaty specifically addressed the status of Nakhchivan. It established that Nakhchivan would remain part of Azerbaijan and confirmed its autonomous status. In contrast to the Treaty of Moscow, Article 5 of the Treaty of Kars specified the parties that agreed on the status of Nakhchivan, namely the governments of Turkey, Azerbaijan, and Armenia.  Article 5 states, “The Turkish Government and the Soviet Governments of Armenia and Azerbaijan are agreed that the region of Nakhichevan, within the limits specified by Annex III to the present Treaty, constitutes an autonomous territory under the protection of Azerbaijan.”

The territory of Nakhchivan was defined within the boundaries specified in Annex III of the treaty. Annex III states, “Territory of Nakhichevan  Village of Ourmia, from there by a straight line to the Azerdaian station (leaving it to SSRA), then by a straight line to Ms. Dash-Burun west (3142), watershed of Mt. Dash-Burun east (4108), crosses the river Kyahaanam-Darassi to the south of the inscription "Rodne" (Boulakh) (South), following the watershed of Mt. Bgarsik (6607) or (6587), and from there follows the administrative border of the former districts of Erivan and of Sharur, Daralagyaz, by the elevation 6629 to the mountain Kemurlu Dagh (6839) or (6930), and from there to the elevation 3080, Sayat Dagh (7868), village Kurt Kulag (Kyurt Kulak), Mt. Gamessur Dagh (8160), elevation 8022, Kuri Dagh (10,181), and the eastern administrative border of the former district of Nakhichevan.”

Thus, the Treaty of Kars completely resolved the status of Nakhchivan (similar to that in the Treaty of Moscow) and its subordination, in the capacity of an international agreement. Signed for unlimited duration, the treaty cannot be unilaterally terminated by any of the signatory states. Under this treaty, the Republic of Turkey took on the role of guarantor for Nakhchivan. The legislative bodies of the signatory nations ratified the Treaty of Kars between March and June 1922, and it officially came into effect on September 11 of that same year.

Despite the declaration of the Nakhchivan region as a Soviet Socialist Republic following the signing of the Treaty of Kars, Armenia attempted to reject this provision under various pretexts and launched territorial claims against Nakhchivan. Between 1929 and 1931, a part of the territory of the Nakhichevan ASSR was illegally transferred to Armenia through resolutions issued by the Transcaucasian Central Executive Committee.  In 1929, the villages of Gurdgulak, Khachik, and Horadiz in Sharur uezd, the Nakhichevan uezd, the Aghbina, Agkhach, Almali, Dag Almali, Itqiran, and Sultanbey villages in the Shahbuz district, the Mehri and Bugakar settlements in Ordubad uezd, which were part of Garchivan selsoviet, and a portion of the Kilit village, a total of 657 square kilometers of land, were transferred to Armenia. In the following years, several territories were annexed to Armenia, and approximately 15% of the territory of the Nakhchivan Autonomous Republic, as established by the international Treaty of Kars, was illegally occupied by Armenia from the 1920s to 1990s.

The foundation for autonomy was established by the Treaty of Moscow, with the parties reaffirming it in the Treaty of Kars, which led to the creation of the Nakhchivan SSR in Nakhchivan territory. However, after the USSR was formed, the Nakhchivan SSR experienced a shift in its political and administrative status on June 16, 1923, when it became the Nakhchivan Region. It wasn't until February 9, 1924, that the region's political and administrative status was reinstated, resulting in its designation as the Nakhchivan ASSR. On November 17, 1990, it was renamed the Nakhchivan Autonomous Republic.

Recommended literature:

1. Naxçıvan tarixinə dair qaynaqlar / AMEA Naxçıvan bölməsi, AMEA Qafqazşünaslıq İnstitutu ; tərt.: İ. Hacıyev, E. H. Kəlbizadə. - Bakı : Elm və təhsil, 2018. - 240 s.
2. Atnur, İbrahim Ethem. Osmanlı idarəçiliyindən Sovet idarəçiliyinə qədər Naxçıvan : 1918-1921 / İ. E. Atnur ; tərc. Q. Əsgərova ; ön sözün müəl. İ. Ə. Həbibbəyli ; elmi red. V. Məmmədov ; Naxçıvan Muxtar Respublikası Ali Məclisi. - Naxçıvan : Əcəmi NPB, 2013. - 496 s.
3. Behbud Ağa Şahtaxtinski və Qars müqaviləsi: 12 oktyabr 2011-ci ildə Behbud ağa Şahtaxtinskinin 130 illik yubileyi və beynəlxalq Qars müqaviləsinin 90-cı ildünümünə həsr olunmuş konfransın materialları /Naxçıvan Muxtar Respublikası, Ali Məclisi. - Naxçıvan: Əcəmi, 2012. - 86 s.
4. Алиев, Намик Гасан оглу. Армянская экспансия и международные договоры по Южному Кавказу в XIX-XX вв.: (Историко-правовое исследование) /Н. Алиев. - Киев: Издательский дом Дмитрия Бураго, 2021. - 183 с.