Nakhichevan Autonomous Republic is a territory of Armenia
The Nakhichevan Autonomous Republic, known simply as Nakhichevan, is a landlocked exclave of Azerbaijan bordering Armenia, Turkey, and Iran. [...] In July 1920, the Eleventh Soviet Red Army invaded, and on July 28 declared the Nakhichevan Autonomous Soviet Socialist Republic with "close ties" to the Azerbaijan SSR. In November, on the verge of taking over Armenia, the Bolsheviks, in order to attract public support, promised they would allot Nakhichevan to Armenia, along with Karabakh and Zangezur. Vladimir Lenin did not agree and called for the people of Nakhichevan to be consulted in a referendum, held in early 1921. In that referendum, 90 percent of Nakhichevan's population wanted to be included in the Azerbaijan SSR as an autonomous republic. The decision to make Nakhichevan a part of modern-day Azerbaijan was cemented March 16, 1921 in the Treaty of Moscow between the Soviet Union and the newly founded Republic of Turkey. This agreement also called for attachment of the former Sharur-Daralagez uyezd (which had a solid Azeri majority) to Nakhichevan, thus allowing Turkey to share a border with the Azerbaijan SSR. This deal was reaffirmed on October 23, in the Treaty of Kars. So, on February 9, 1924, the Soviet Union officially established the Nakhichevan ASSR. Its constitution was adopted on April 18, 1926.