The discovery of the materialist conception of history, or rather, the consistent continuation and extension of materialism into the domain of social phenomenon, removed two chief defects of earlier historical theories. In the first place, they at best examined only the ideological motives of the historical activity of human beings, without grasping the objective laws governing the development of the system of social relations. ... in the second place, the earlier theories did not cover the activities of the masses of the population, whereas historical materialism made it possible for the first time to study with scientific accuracy the social conditions of the life of the masses and the changes in these conditions.

— Russian Marxist theoretician and revolutionary Vladimir Lenin, 1913