Leninism is the political theory for the organisation of a revolutionary vanguard party and the achievement of a dictatorship of the proletariat, as political prelude to the establishment of socialism. Developed by and named for the Russian revolutionary Lenin, Leninism comprises socialist political and economic theories, developed from Marxism, and Lenin's interpretations of Marxist theories, for practical application to the socio-political conditions of the Russian Empire of the early 20th century.
Functionally, the Leninist vanguard party was to provide the working class with the political consciousness (education and organisation) and revolutionary leadership necessary to depose capitalism in Imperial Russia. After the October Revolution of 1917, Leninism was the dominant version of Marxism in Russia, and, in establishing soviet democracy, the Bolshevik régime suppressed Marxists who opposed the revolution, such as the Mensheviks and factions of the Socialist Revolutionary Party. The Russian Civil War (1917–22) thus included left-wing uprisings against the Bolsheviks (1918–1924) that were suppressed in the Russian Socialist Federative Soviet Republic (RSFSR), before incorporation to the Union of Soviet Socialist Republics (USSR) in 1922.
Leninism was composed as and for revolutionary praxis, and originally was neither a rigorously proper philosophy nor a discrete political theory; after the Russian Revolution, in History and Class Consciousness: Studies in Marxist Dialectics (1923), György Lukács developed and organised Lenin's pragmatic revolutionary practices and ideology into the formal philosophy of vanguard-party revolution (Leninism). As a political-science term, Leninism entered common usage in 1922, after infirmity ended Lenin's participation in governing the Russian Communist Party. Two years later, in July 1924, at the fifth congress of the Communist International, Grigory Zinoviev popularized the term Leninism to denote "vanguard-party revolution".