how did the communists establish control in the new union of soviet socialist republics
The Communist Party of the Soviet Union (Russian: Коммунисти́ческая па́ртия Сове́тского Сою́за, tr. Kommunistícheskaya pártiya Sovétskogo Soyúza, IPA: (kəmʊnjɪsjtjˈitɕɪskəjə ˈpartjɪjə sɐvjˈetskəvə sɐˈjuzə)), abbreviated in English as CPSU (Russian: КПСС, tr. KPSS) was the founding and ruling political party of the Union of Soviet Socialist Republics (USSR or Soviet Union). The CPSU was the sole governing party of the Soviet Union until 1990, when the Congress of People's Deputies modified the article of the constitution which had granted the CPSU a monopoly over the political system. The party was founded in 1912 by the Bolsheviks (a faction of the Russian Social Democratic Labour Party, RSDLP), a revolutionary group led by Vladimir Lenin which seized power in the aftermath of the October Revolution of 1917. The party was dissolved on 29 August 1991 on Soviet territory soon after a failed coup d'état and was completely abolished on 6 November 1991 on Russian territory. It also controlled the world's largest armed forces, the Armed Forces of the Soviet Union.