On 30th December 1922, following the Russian Revolution, the Union of Soviet Socialist Republics (USSR) was formed. This resulted in the merger of Russia, Belorussia, Ukraine, and the Transcaucasian Federation into one large country. In the decades that followed, the Soviet Union, as it was commonly known, developed into one of the most powerful and influential countries in the world. It eventually dissolved into several separate nations in 1991.

During its 69 years of history, the USSR was the largest country on Earth. It spanned the distance from the Baltic Sea in the west to the Pacific Ocean in the east, covering 11 time zones. Due to the amalgamation of several countries, the USSR contained over 100 different ethnic groups that spoke over 130 languages.

The USSR was run by the 'Politburo', a coalition of 12-15 communist representatives, including a chairman. They controlled the economy, including the cost of goods and established five year plans that set targets for the Soviet Union.

The first leader of the USSR was Vladimir Lenin (1870-1924), whose slogan "Peace, love and bread" and Communist ideals quickly gained popularity across the nation. After Lenin's death, Joseph Stalin (1878-1953) took his place, followed by Nikita Khrushchev (1898-1971) and Leonid Brezhnev (1906-1982). The final leader, Mikhail Gorbachev (born 1931), led the Soviet Union to its dissolution in 1991, when the Union separated into 15 sovereign states.

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