A distinct variant of Marxism formulated by Lenin, who prior to the Bolshevik revolution argued for direct rule by workers and peasants, and advocated direct democracy through the soviets (councils). In practice, the Bolshevik revolution did not produce a democratic republic, but gave a 'leading and directing' role to the party, seen as the vanguard of a working class which had insufficient political consciousness to forge a revolution; such a well-organized and disciplined party, operating according to the principles of democratic centralism, would be able to exploit the revolutionary situation.
Leninist principles of a revolutionary vanguard became the central tenet of all communist parties. All were organized according to the idea of democratic centralism which affords the leadership, on the grounds of their revolutionary insight, the right to dictate party policy, to select party officials from above, and to discipline dissenting party members.
Lenin modified Marx's theory of historical materialism, contending that revolutionary opportunities should be seized when they arose, and not when the social and economic conditions of capitalist crisis leading to proletarian revolution existed. He also developed a theory of imperialism which held that it was the last stage of a decaying capitalism. This was used to justify revolution in feudal Russia, because it was an imperial power, and since then to justify communist intervention in underdeveloped countries as part of the struggle between socialism and imperialism.