Wilhelm Friedrich Georg Roscher (1817–94) is generally remembered as a significant nineteenth-century German political economist and a contributor to the “German historical school of economics.” His work is usually placed in the context of a larger narrative about the development of economic thought. Yet intellectual historians have rarely noticed that, for Roscher, Staatswirthschaft or Nationalökonomie were subordinate to a larger science of politics, and few have engaged with the substance of his political thought (as opposed to his economics). The aim of this article is to provide an interpretation of Roscher as a political thinker, focusing especially on his account of the modern European state between the 1840s and the 1890s. In particular, it explores Roscher's concern that nineteenth-century Europe's economically advanced societies, characterized by an unstable combination of democratic sovereignty, deep socio-economic inequality and a centralized state apparatus, would soon find themselves at the mercy of “military tyranny” or “Caesarism.” It underlines the ways in which Roscher's preoccupation with ancient history fed into his estimation of nineteenth-century politics, and also examines his comparative assessment of democracy's prospects in Britain, France and the United States.