Video: '30th December 1922: Foundation of the USSR'

(Saturday, December 30, 1922; during the Russian Civil War, part of the Russian Revolution and the aftermath of World War I) — The Union of Soviet Socialist Republics (referred to alternatively as the USSR or the Soviet Union) was created today as a new nation  2,215 delegates of the First All-Union Congress of Soviets ratified the Treaty on the Formation of the Union of Soviet Socialist Republics.

The Congress, based on proportional representation, was comprised of 1,727 persons from the Russian SFSR, 364 from the Ukrainian SSR, 91 from the Transcaucasian SSR (consisting of the SSRs of Armenia, Azerbaijan, and Georgia), and 33 from the Byelorussian SSR.

The delegates, who gathered at the Bolshoi Theater in Moscow, elected a four-member Central Executive Committee to act on behalf of the nation between sessions of the Congress of Soviets, consisting of Mikhail Kalinin (Russia), who was elected Chairman; Grigory Petrovsky (Ukraine); Nariman Narimanov (of Azerbaijan, for the Transcaucasian SSR); and Alexander Chervyakov (Byelorussia, later Belarus).

A flagship communist state, it was nominally a federal union, ultimately comprising fifteen top-level republics; in practice, both its government and its economy were built on a highly centralized model until its final years.

It was a one-party state governed by the Communist Party of the Soviet Union, with Moscow as the capital.

The Soviet Union was the largest country in the world by land area, covering over 8,649,500 square miles and spanning eleven time zones.

The USSR would exist for almost 69 years, being formally dissolved on December 26, 1991.