The Russian Soviet Federative Socialist Republic, previously known as the Russian Soviet Republic and the Russian Socialist Federative Soviet Republic, as well as being unofficially referred to as Soviet Russia, the Russian Federation, or simply Russia, was an independent federal socialist state from 1917 to 1922, and afterwards the largest and most populous constituent republic of the Soviet Union (USSR) from 1922 to 1991, until becoming a sovereign part of the Soviet Union with priority of Russian laws over Union-level legislation in 1990 and 1991, the last two years of the existence of the USSR. The Russian SFSR was composed of sixteen smaller constituent units of autonomous republics, five autonomous oblasts, ten autonomous okrugs, six krais and forty oblasts. Russians formed the largest ethnic group. The capital of the Russian SFSR and the USSR as a whole was Moscow and the other major urban centers included Leningrad, Stalingrad, Novosibirsk, Sverdlovsk, Gorky and Kuybyshev. It was the first socialist state in the world.

A socialist state, socialist republic, or socialist country, sometimes referred to as a workers' state or workers' republic, is a sovereign state constitutionally dedicated to the establishment of socialism. The term communist state is often used synonymously in the West, specifically when referring to one-party socialist states governed by Marxist–Leninist communist parties, despite these countries being officially socialist states in the process of building socialism and progressing toward a communist society. These countries never describe themselves as communist nor as having implemented a communist society. Additionally, a number of countries that are multi-party capitalist states make references to socialism in their constitutions, in most cases alluding to the building of a socialist society, naming socialism, claiming to be a socialist state, or including the term people's republic or socialist republic in their country's full name, although this does not necessarily reflect the structure and development paths of these countries' political and economic systems. Currently, these countries include Algeria, Bangladesh, Guyana, India, Nepal, Nicaragua, Sri Lanka and Tanzania.