Ukrainian Soviet Socialist Republic
Eventually, after the creation of the Communist Party (Bolshevik) of Ukraine in Moscow, a third Ukrainian Soviet government was formed on 21 December 1919 that initiated new hostilities against Ukrainian nationalists as they lost their military support from the defeated Central Powers. Eventually, the Red Army ended up controlling much of the Ukrainian territory after the Polish-Soviet Peace of Riga. On 30 December 1922, along with the Russian, Byelorussian, and Transcaucasian republics, the Ukrainian SSR was one of the founding members of the Union of Soviet Socialist Republics (USSR).
Communist Party of Ukraine (Soviet Union)
Most of its constituent members were former members of the Russian Bolsheviks who in 1917 pronounced themselves "RSDRP(b) – Social-Democracy of Ukraine" and with the help of the Antonov-Ovseyenko expeditionary forces of Petrograd and Moscow Red Guards instigated a civil war in Ukraine by routing local Red Guards. Number of Ukrainian politicians from left faction of the Ukrainian Social Democratic Labour Party (also known as Left Ukrainian Social Democrats or unofficially as "Ukrainian Bolsheviks") joined the Bolsheviks in January 1918.