The Soviet Union, officially the Union of Soviet Socialist Republics (USSR), was a country in Eurasia. It was nominally a supranational union of national republics, but its governance and economy were highly centralized in a state that was unitary in most respects. Although each member republic had its own communist party, the Union was a one-party state, federal in nature and governed by the all-Union party, the Communist Party of the Soviet Union. Although Russia, the Union's largest member, was not explicitly privileged by law, the Russian nation was in some respects culturally, politically and linguistically dominant. Member states included Russia, Ukraine, Byelorussia, Uzbekistan, Kazakhstan, Georgia, Azerbaijan, Lithuania, Moldavia, Latvia, Kighizia, Tajikistan, Armenia, Turkmenia and Estonia. The Union's capital and most populous city was Moscow, located in the west of the country, in its European region.
- Soviet Union on Wikipedia