National delimitation in the Union of Soviet Socialist Republics was the process of specifying well-defined national territorial units (Soviet socialist republics [SSR], autonomous Soviet socialist republics [ASSR], autonomous oblasts [provinces], raions [districts] and okrugs [circuits]) from the ethnic diversity of the Union of Soviet Socialist Republics (USSR) and its subregions.
The Russian-language term for this Soviet state policy was razmezhevanie (Russian: национально-территориальное размежевание, natsionalno-territorialnoye razmezhevaniye), which is variously translated in English-language literature as "national-territorial delimitation" (NTD), "demarcation", or "partition".[1] 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.[2]
National delimitation in the USSR was distinct from nation-building (Russian: национальное строительство), 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).