The Soviet Union was officially created in 1922, however, if there was a date which could be considered as a birthday of the USSR, that would have had to be November 7th of 1917 — this was the day when in St Petersburg the Bolsheviks — the organised military revolutionaries, who later became the Communist Party of the USSR — came to power. The Russian Provisional Government which were the head of the country after the Tsar Nicholas II had resigned, was overthrown and the Soviets, taking the government buildings one by one, had finally captured the town.
Happy Birthday Dear USSR! The Great October Socialist Revolution. November 7th 1917.
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