The history of capitalism is the history of the world's population being transformed into proletarian existence

While work is common to every society, under capitalism it takes on historically unique qualities. In pre-capitalist societies, work was necessary, but people had shared access to land, subsistence farming and the necessary means of survival. Peasants were poor but self-sufficient, and survival was not dependent on working for someone else. Capitalism changed all this. Through the process called primitive accumulation, pre-capitalist workers were uprooted from their land and dispossessed of their means of subsistence. Peasants struggled against this and continued to survive on the margins of the emerging capitalist world, and it eventually took violent force and harsh new legal systems to impose wage labour on the population. Peasants, in other words, had to be made into a proletariat. This new figure of the proletariat was defined by its lack of access to the means of production or subsistence, and its requirement for wage labour in order to survive. This means that the 'proletariat' is not just the 'working class' nor is it defined by an income level, profession of culture. Rather, the proletariat is simply that group of people who must sell their labour power to live – whether they are employed or not.. And the history of capitalism is the history of the world's population being transformed into proletarian existence through the advancing dispossession of the peasantry.

Nick Srnicek & Alex Williams, Inventing the Future (Verso, 2016) pp. 86-87