According to Hobbes, a commonwealth can only occur when the natural multitude of men are made one thanks to a covenantal device. The artificial unity of the political community can be seen as strengthened by the use of concepts that reflect some natural unity, such as “body” or “person”. Both notions can indeed be found in Hobbes’s political treatises, but the degree of importance attached to them varies greatly. The key to this evolution is to be found in De cive, where Hobbes explicitly dismisses the notion of a body politic and substitutes the concept of person for it. This paper examines the significance of this conceptual change by following its trajectory from Elements of Law to Leviathan and discussing its implications for Hobbes’s understanding of civil unity.