In the Soviet Union, national delimitation was the process of specifying well-defined national territorial units (Union Republics [SSR], Autonomous Soviet Socialist Republics [ASSR], autonomous oblasts [provinces], raions [districts] and okrugs [circuits]) from the ethnic diversity of the USSR and its subregions.

The Russian-language term for this Soviet state policy was razmezhevanie (from , natsionalno-territorialnoye razmezhevaniye), which is variously translated in English-language literature as "national-territorial delimitation" (NTD), "demarcation", or "partition".Hasan Ali Karasar, "The Partition of Khorezm and the Positions of Turkestanis on Razmezhevanie", Europe-Asia Studies, 60(7):1247-1260 (September 2008). National delimitation formed part of a broader process of changes in administrative-territorial division, which also changed the boundaries of territorial units, but was not necessarily linked to national or ethnic considerations.Тархов, Сергей. Изменение административно-территориального деления России в XII-XX в.

National delimitation in the USSR was distinct from nation-building (), which typically referred to the policies and actions implemented by the government of a national territorial unit (a nation state) after delimitation. In most cases national delimitation in the USSR was followed by korenizatsiya (indigenization).

Policies of national delimitation in the Soviet Union

Pre-1917 Russia was a multiethnic empire, not a nation state. In the 1905 Duma elections the nationalist parties received only 9 percent of all votes. Many non-Russian indigenous ethnic groups in the Russian Empire were classified as inorodtsy (literally meaning "of different, i.e., non-Russian descent"). After the February Revolution, attitudes in regards to this topic began to change. In early 1917, a Socialist Revolutionary publication called Dyelo Naroda, No. 5 called for Russia to be transformed into a federal state along the lines of the United States. Specifically, separate constituent units inside of this federal state would be created for the various regions and ethnic groups of Russia (such as Little Russia, Georgia, Siberia, and Turkestan).

The Soviet Russia that took over from the Russian Empire in 1917 was not a nation-state, nor was the Soviet leadership committed to turning their country into such a state. In the early Soviet period, even voluntary assimilation was actively discouraged, and the promotion of the national self-consciousness of the non-Russian populations was attempted. Each officially recognized ethnic minority, however small, was granted its own national territory where it enjoyed a certain degree of autonomy, national schools, and national elites. A written national language (if it had been lacking), national language planning, native-language press, and books written in the native language came with the national territory, along with cultural institutions such as theaters.Slezkine, Yuri (1994). "The USSR as a Communal Apartment, or How a Socialist State Promoted Ethnic Particularism" . Slavic Review 53 (2), 414–52. The attitudes towards many ethnic minorities changed dramatically in the 1930s–1940s under the leadership of Joseph Stalin (despite his own Georgian ethnic roots) with the advent of a repressive policy featuring abolition of the national institutions, ethnic deportations, national terror, and Russification (mostly towards those with cross-border ethnic ties to foreign nation-states in the 1930s or compromised in the view of Stalin during the Great Patriotic War in the 1940s), although nation-building often continued simultaneously for others.Martin, Terry (1998). "The Origins of Soviet Ethnic Cleansing" . The Journal of Modern History 70 (4), 813-861. After the establishment of the Soviet Union within the boundaries of the former Russian Empire, the Bolshevik government began the process of national delimitation and nation building, which lasted through the 1920s and most of the 1930s. The project attempted to build nations out of the numerous ethnic groups in the Soviet Union. Defining a nation or politically conscious ethnic group was in itself a politically charged issue in the Soviet Union. In 1913, Stalin, in his work Marxism and the National Question, which subsequently became the cornerstone of the Soviet policy towards nationalities, defined a nation as "a historically constituted, stable community of people, formed on the basis of a common language, territory, economic life, and psychological makeup manifested in a common culture".Definition of a nation in J. Stalin, Marxism and the National Question , March–May 1913; Russian original: J. Stalin, Collected Works in 16 Volumes, volume 2 . Many of the subject nationalities or communities in the Russian Empire did not fully meet these criteria. Not only did cultural, linguistic, religious and tribal diversities make the process difficult, but also the lack of a political consciousness of ethnicity among the people was a major obstacle. The process relied on the Declaration of the Rights of the Peoples of Russia, adopted by the Bolshevik government on 15 November 1917, immediately after the October Revolution, which recognized equality and sovereignty of all the peoples of Russia; their right for free self-determination, up to and including secession and creation of an independent state; freedom of religion; and free development of national minorities and ethnic groups on the territory of Russia.Declaration of Rights of the Peoples of Russia , 15 November 1917, Big Soviet Encyclopedia, on-line edition. Retrieved 15 November 2008.

The Soviet Union (or more formally USSR – the Union of Soviet Socialist Republics) was established in 1922 as a federation of nationalities, which eventually came to encompass 15 major national territories, each organized as a Union-level republic (Soviet Socialist Republic or SSR). All 15 national republics, created between 1917 and 1940, had constitutionally equal rights and equal standing in the formal structure of state power. The largest of the 15 republics – Russia – was ethnically the most diverse and from the very beginning it was constituted as the RSFSR – the Russian Soviet Federative Socialist Republic, a federation within a federation. The Russian SFSR was divided in the early 1920s into some 30 autonomous ethnic territories (Autonomous Soviet Socialist Republics – ASSR and autonomous oblasts – AO), many of which exist to this day as ethnic republics within the Russian Federation. There was also a very large number of lower-level ethnic territories, such as national districts and national village soviets. The exact number of ASSR and AO varied over the years as new entities were created while old entities switched from one form to another, transformed into Union-level republics (e.g., Kazakh and Kyrgyz SSR created in 1936, Moldovan SSR created in 1940), or were absorbed into larger territories (e.g., Crimean ASSR absorbed into the RSFSR in 1945 and Volga German ASSR absorbed into RSFSR in 1941).

RepublicMap of the Union Republics between 1956 and 1991123456789101112131415

The first population census of the USSR in 1926 listed 176 distinct nationalities.List of nationalities in the 1926 USSR census on demoscrope.ru Eliminating excessive detail (e.g., four ethnic groups for Jews and five ethnic groups for Georgians) and omitting very small ethnic groups, the list was condensed into 69 nationalities.Gerhard Simon, Nationalism and Policy Toward the Nationalities in the Soviet Union: From Totalitarian Dictatorship to Post-Stalinist Society, Westview Press, Boulder, CO, 1991. These 69 nationalities lived in 45 nationally delimited territories, including 16 Union-level republics (SSR) for the major nationalities, 23 autonomous regions (18 ASSR and 5 autonomous oblasts) for other nationalities within the Russian SFSR, and 6 autonomous regions within other Union-level republics (one in Uzbek SSR, one in Azerbaijan SSR, one in Tajik SSR, and three in Georgian SSR).

Higher-level autonomous national territories in the Soviet Union Host republic Host titular nations Type Name Creation date Titular nations Russian SFSR Russians Autonomous republic Bashkir ASSR 1919 Bashkirs Autonomous republic Buryat ASSR 1923 Buryats Autonomous republic Chechen-Ingush ASSR 1936 Chechens and Ingush people Autonomous republic Chuvash ASSR 1925 Chuvash people Autonomous republic Crimean ASSR 1921–1945 Crimean Tatars Autonomous republic Dagestan ASSR 1921 Aghul, Avars, Dargins, Kumyks, Laks, Lezgins, Nogais, Rutuls, Tabasarans, and Tsakhurs Autonomous republic Kabardino-Balkar ASSR 1921 Kabarday and Balkars Autonomous republic Kalmyk ASSR 1935 Kalmyks Autonomous republic Karelian ASSR 1923 Karelians Autonomous republic Komi ASSR 1921 Komi peoples Autonomous republic Mari ASSR 1920 Mari people Autonomous republic Mordovian ASSR 1930 Mordvins Autonomous republic North Ossetian ASSR 1924 Ossetians Autonomous republic Udmurt ASSR 1920 Udmurts Autonomous republic Volga German ASSR 1918–1941 Volga Germans Autonomous republic Tatar ASSR 1920 Tatars Autonomous republic Turkestan ASSR 1918–1924 Turkic peoples of Central Asia Autonomous republic Tuva ASSR 1961 Tuvans Autonomous republic Yakut ASSR 1922 Yakuts Autonomous oblast Adyghe AO 1922 Adyghe people Autonomous oblast Gorno-Altai AO (Oyrot AO until 1948) 1922 Altai people Autonomous oblast Jewish AO 1934 Jews Autonomous oblast Karachay–Cherkess AO 1922 Karachays and Cherkess Autonomous oblast Khakas AO 1930 Khakas peopleGeorgia Georgians Autonomous republic Abkhaz ASSR 1931 (Abkhazian SSR 1921–1931) Abkhazians Autonomous republic Adjar ASSR 1921 Adjarians Autonomous oblast South Ossetian AO 1922 OssetiansAzerbaijan Azerbaijanis Autonomous republic Nakhichevan ASSR 1920 mixed Azerbaijani–Armenian region Autonomous oblast Nagorno-Karabakh AO 1923 ArmeniansUkraine Ukrainians Autonomous republic Moldavian ASSR 1924–1940 Moldovans Autonomous republic Crimean ASSR 1991 undefined Uzbekistan Uzbeks Autonomous republic Karakalpak ASSR 1925 (Karakalpak AO until 1932) Karakalpaks Tajikistan Tajiks Autonomous oblast Gorno-Badakhshan AO 1929 Pamiris

Despite the general policy of granting national territories to all ethnic groups, several nationalities remained without their own territories in the 1920s and the 1930s. In many cases these groups were either widely dispersed, or these minorities were concentrated in areas already designated as the national republic for a different group. For example, Poles and Jews (who were considered a nationality) represented up to a third of the population in some areas of the Ukrainian or Byelorussian SSRs or nearly half of the population in some cities and towns, yet apart from national raions, 24 of which were established in the Ukrainian SSR, no particular territorial entity was created (though a Jewish Autonomous Oblast was established in the Russian Far East in 1934). For the largely Yiddish-speaking Jews in these areas, policies were implemented such as the designation of Yiddish as an official language of Byelorussian SSR and a corresponding national public education system in Yiddish, along with the promotion of Yiddish literature and theatre in these areas as well as in the larger Russian cities. Other minorities included Bulgarians, Greeks, Hungarians, Romani, Uigurs, Koreans, and Gagauz (today the Gagauz live in a compact area known as Gagauzia in the south of Moldova, where they enjoy a measure of autonomy). The Volga Germans lost their national territory with the outbreak of World War II in 1941. The peoples of the North had neither autonomous republics nor autonomous oblasts, but since the 1930s they have been organized in 10 national autonomous okrugs for the Chukotka, Koryak, Nenets, Dolgano-Nenets, Yamalo-Nenets, Khanty-Mansi, Agin-Buryat, Ust-Orda Buryat, Evenk, Komi-Permyak titular nations.