The revolution of 1917 led to serious changes in the entire spectrum of political parties in Russia. Since the end of 1917, the RSDLP (B) has begun implementing a number of tough measures against its political opponents. On November 28, 1917, the SNK adopted a decree that outlawed the Cadet party. Its leaders were subject to arrest, and the periodical press closed. The dictatorship of a single political party is gradually taking shape. The tactical block of the Bolsheviks with the Left Social Revolutionaries was not long.

After the dissolution of the Constituent Assembly, the Mensheviks and Social Revolutionaries attempted to transfer the struggle to strengthen their political influence to the masses and joined the re-election campaign for the Soviets. The latter, as they believed, turned into a “voting machine,” mechanically, without any discussion, stamping decrees.

To improve the Soviets and to strengthen their permanent contact with the masses was resolved through the creation in Petrograd of the movement authorized by factories and plants. This idea arose on the initiative of the Menshevik Central Committee. In March 1918, the first meeting of the Assembly of Commissioners was held, attended by representatives of 24 Petrograd factories and plants. The outlined change in the mood of the workers had to recognize G. Ye. Zinoviev, who declared in May 1918 that the district Soviets had become "chambers of lords", and "the assembly of commissioners has reason to accuse the Soviets of separation from the broad masses of workers".

However, the Assembly of Commissioners did not succeed in becoming a mass movement. In the summer of 1918, there were arrests of its leaders and the opposition wave was somewhat asleep. At the same time, the political crisis of the spring of 1918 showed the Bolshevik leadership the need to establish closer ties between the party and the working masses. The participation of leading party officials in the conduct of economic policy is becoming increasingly tangible, turning into widespread intervention.

The supreme and central government departments (Council of People's Commissars, the Council of Defense, People's Commissariats) acted as direct agents of the party’s policy. The functions of the party increasingly merged with the functions of the state apparatus, and the party itself became more and more “bureaucratic”. According to information collected by the Ninth Congress of the RCP (B.), 53% of the Bolsheviks were employees of Soviet institutions; only 11% of the communists worked in factories. Vividly manifested desire and "okommunisticichivaniyu" Soviets. Among the delegates of the VI-VIII All-Russian Congresses of the Soviets, the Bolsheviks accounted for over 96-98% of all participants, and as part of individual provincial congresses of the Soviets - up to 99%.

In 1920-1921 The RCP (B.) Strengthened the work aimed at splitting the various "anti-Soviet" parties, above all the Mensheviks and Socialist Revolutionaries. For this, an extensive network of whistleblowers was created. Thus, at a meeting of the Petrograd provincial Cheka on November 17, 1921, it was reported about the number of registered representatives of various parties: about 100 right-wing Socialist-Revolutionaries, 187 left-wing Social Revolutionaries, etc. Number of informants in the city’s factories and factories According to the chief of the Information Department of the Cheka, by that time was determined by the figure of 600 people. Of these, 422 were members of the RCP (B).

During this period, the process of self-liquidation of a number of parties was actively developed. In November 1919, the congress of the social democrats-internationalists announced the liquidation of their party and joining the ranks of the Bolsheviks. In April 1920, the same decision was made by the conference of the Union of Maximist Socialist Revolutionaries. In the spring of 1920, self-dissolving and joined the RCP (b) the Ukrainian Borotbist Party; in March 1921 a similar step was taken by the Bund.

In March 1921, at the 10th Congress of the RCP (B), where the landmark resolution "On Party Unity" was adopted, Lenin directly stated: "We, after two and a half years of Soviet power, spoke before the whole world and told the Communist International that the dictatorship of the proletariat is impossible otherwise than through the Communist Party. "

By the beginning of 1922, that form of political organization took shape in the country, which at the XII Congress of the RCP (B) was called the "dictatorship of the party". In the summer of the same year, a trial was held over the Right Social Revolutionaries. The process had a propaganda goal. He had to show the people how perverse any political opposition to the Soviet government was. The leadership of the Socialist-Revolutionary Party was accused, in particular, of organizing terrorist acts against the Bolshevik leaders in 1918 (the murder of M. Uritzky and V. Volodarsky, the attempt on V. I. Lenin).

In August 1922, the tribunal issued the death sentence to twelve defendants of the first group, among whom were 8 members of the Central Committee of the party: A. R. Gotz, M. Ya. Gendelman, N. N. Ivanov, E. M. Timofeev, and others. Speaking at in his last word, T-Mofeyev said: "You will get our heads to put them at the feet of the Comintern, but you will not receive our honor." Some time later, the death sentence of the accused was replaced with various prison sentences. In early 1924, all prisoners in the process were amnestied.

At the 12th All-Russian Party Conference held in August 1922, a special resolution "On anti-Soviet parties and trends" was adopted, which effectively sanctioned the use of repression against politically dissent, justifying it with "revolutionary expediency" in the cause of "suppressing those obsolete groups who try to seize the old positions won back from the proletariat. " Thus, the phrase of M. P. Tomsky who spoke at the XI Congress of the RCP (b) in April 1922 that "we have multiparty parties. But unlike in foreign countries, we have one party in power and the rest in prison", only summed up the process of folding the "dictatorship of the party."

In early January 1923, the bureau of the Petrograd Provincial Committee of the RCP (B.) Allowed the "Socialist-Revolutionary Initiative Group" (under the tacit control of the GPU) to hold a city meeting. As a result, the planned result was achieved - the decision to dissolve the city organization of the Socialist Revolutionary Party. In March 1923, with the participation of "Petrograd Initiatives", the All-Russian Congress of former rank-and-file members of the Socialist Revolutionary Party was held, which deprived the former leadership of the party of powers and announced its dissolution. The Socialist-Revolutionary Party, and soon its regional organizations, ceased to exist. Similarly, in the years 1923-1924. the Menshevik organizations self-dissolve.