Claim: The Communist Party of the Soviet Union attempted a coup.

The Communist Party of the Soviet Union , abbreviated in English as CPSU , was the founding and ruling political party of the Union of Soviet Socialist Republics -LRB- USSR or Soviet Union -RRB- . 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 -LRB- the majority faction of the Russian Social Democratic Labour Party -RRB- , 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 .   The CPSU was a communist party organized on the basis of democratic centralism , a principle conceived by Lenin that entails democratic and open discussion of policy issues within the party followed by the requirement of total unity in upholding the agreed policies . The highest body within the CPSU was the party Congress , which convened every five years . When the Congress was not in session , the Central Committee was the highest body . Because the Central Committee met twice a year , most day-to-day duties and responsibilities were vested in the Politburo , the Secretariat , and the Orgburo -LRB- until 1952 -RRB- . The party leader was the head of government and held the office of either General Secretary , Premier or head of state , or some of the three offices concurrentlybut never all three at the same time . The party leader was the de facto chairman of the CPSU Politburo and chief executive of the USSR ; the tension between the party and the state -LRB- Council of Ministers of the Soviet Union -RRB- for the shifting locus of power was never formally resolved , but in reality the party dominated , and a paramount leader always existed -LRB- first Lenin and thereafter the General Secretary -RRB- .   The CPSU , according to its party statute , adhered to Marxism -- Leninism , an ideology based on the writings of Vladimir Lenin and Karl Marx , and formalized under Joseph Stalin . The party pursued state socialism , under which all industries were nationalized and a planned economy was implemented . Before central planning was adopted in 1929 , Lenin had introduced a mixed economy , commonly referred to as the New Economic Policy , in the 1920s , which allowed to introduce certain capitalist elements in the Soviet economy . After Mikhail Gorbachev took power in 1985 , at first trying to prop up the stagnant centrally planned economy , rapid steps were taken to transform the economic system in the direction of a market economy . Gorbachev and some of his allies envisioned the introduction of an economy similar to Lenin 's New Economic Policy through a program of perestroika , or restructuring , but the results of their reforms contributed to the fall of the entire system of government .   A number of causes contributed to CPSU 's loss of control and the dissolution of the Soviet Union . Some historians have written that Gorbachev 's policy of glasnost -LRB- political openness -RRB- was the root cause , noting that it weakened the party 's control over society . Gorbachev maintained that perestroika without glasnost was doomed to failure anyway . Others have blamed the economic stagnation and subsequent loss of faith by the general populace in communist ideology .