proletariat, in Marxian theory, the class of exploited workers and wage earners who depend on the sale of their labor for their means of existence. In ancient Rome, the proletariat was the lowest class of citizens; its members had no property or assured income and were a source of discontent and political instability. According to Karl Marx, the breakup of feudalism and the development of capitalism created a new, propertyless class from the dispossessed peasants and retainers who were forced to sell their labor for wages in the new industrial centers. Marx believed that the seizure of power by the proletariat from the capitalist class was a necessary step to a classless society. Under Lenin and the Bolsheviks, this revolution was to be directed by the Communist party, as the vanguard of the dictatorship of the proletariat.

The lowest, or one among the lowest, economic and social classes in a society. In ancient Rome, the proletariat were poor landless freemen who, crowded out of the labour market by the extension of slavery, became parasites on the economy. Karl Marx used the term to refer to the class of wage earners engaged in industrial production only (the broader term working class included all those obliged to work for a living). Another of Marx's categories, the lumpenproletariat (lumpen meaning “rags”), comprised marginal and unemployable workers, paupers, beggars, and criminals. Marxian theory predicted a transitional phase between the abolition of capitalism and the establishment of communism during which a “dictatorship of the proletariat” would suppress resistance to the socialist revolution by the bourgeoisie, destroy the social relations of production underlying the class system, and create a new, classless society.

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