Soviet Union
On 28 December 1922, people from the Russian SFSR, the Transcaucasian SFSR, the Ukrainian SSR, and the Byelorussian SSR approved the Treaty of Creation of the USSR and the Declaration of the Creation of the USSR, creating the Union of Soviet Socialist Republics. These two documents were made true by the 1st Congress of Soviets of the USSR and signed by heads of delegations.