The answer is:
The Russian Revolution was a combination of drastic rebellions to replace a Tsarist oppressive regime in 1917. As a result, the dismantlement of Tsar Nicholas II's rule of absolute power led to the creation of the Union of Soviet Socialist Republics in 1922.
Besides, the peace Treaty of Brest-Litovsk was signed in 1918 between Russia's Bolshevik government and the Central Powers of Germany and their allies. The negociation agreed the Russia's participation in World War I.