Autonomous republics and oblasts of the Soviet Union

An autonomous republic of the Union of Soviet Socialist Republics, styled Autonomous Soviet Socialist Republic (ASSR, Russian: автономная советская социалистическая республика, АССР, romanized: avtonomnaya sovetskaya sotsialisticheskaya respublika), was a type of administrative unit created for certain ethnic groups to be the titular nations of. The ASSRs had a status lower than the constituent union republics of the USSR, but higher than the autonomous oblasts and the autonomous okrugs.

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