This article engages with scholars working on the history of capitalism and with scholars of American political development to form a historical materialist perspective on the creation of the American federal government. First, it returns to the debate about the state in capitalist society to develop an approach for theorizing the relations between class, capitalism, and states. Next, it addresses the position of American capitalism in the 1780s, arguing that it was still in a long transition phase. After this, it reinterprets the Constitutional Convention of 1787 in the context of the long and uneven history of American capitalist development. I argue that the U.S. Constitution created the foundations of a state that would serve capitalist interests, including capitalist slave owners, but, at the same time, provided some space for social relations of production not yet fully subordinated to the power of capitalism to coexist.