This paper investigates the differences between the theory of capitalism which underlies the Manifesto of the Communist Party (1848) and the one formulated in Marx’s “critique of political economy”. The differences in question concern (i) the historical origin of capitalism, (ii) long-term prospects of the working class under capitalism, and (iii) the fundamental nature of capitalist social reality. With respect to the first point, while the Manifesto views the emergence of capitalism as based in the expansion of commodity production and trade, Capital emphasizes the expropriation of immediate producers. Secondly, the 1848 text anticipates a worsening, in absolute terms, of the condition of the working class under capitalism. In contrast, Marx’s later account of accumulation allows for the growth of real wages and predicts a relative worsening of the position of the working class. And thirdly, while the Manifesto views capitalism as having made exploitation easier to discern, in Capital the focus is on fetishism and the “topsy-turvy” forms of appearance which mask the nature of social reality. As I argue, these differences are significant enough to speak of two different theories, and they boil down to the way the theories conceive of their object. On all three dimensions analyzed here – history, dynamics, and nature – Capital emphasizes the historical specificity of the capitalist mode of production in ways the Maniefsto did not account for.