Historians, anthropologists, archaeologists, and others continue to produce accounts of "state formation" in numerous pre-modern and non-western settings, from ancient Egypt and Mesoptamia to the pre-Columbian Americas and early China. But just how meaningful is it to speak of "states" in non-modern worlds? This chapter makes a new case for seeing the state as an essentially modern phenomenon. It begins by reviewing various accounts of the ontological status of the state as an entity. Of these, the most theoretically satisfying is Timothy Mitchell's case for seeing the state as an "effect," whereby common-sense presuppositions entangle with political practices to produce the experience of an agency that appears to be ontologically detached from the "society" that it rules. If so, the state is a phenomenon that is realizable only under the peculiar conditions of a modern metaphysical environment, one founded on historically anomalous commitments to materialism, anthropocentrism, secularism, and individualism. To substantiate to point, the chapter considers two non-modern cases, showing how a "state effect" was unrealizable under the radically different metaphysical conditions of Ming China and classical Athens. Accordingly, to understand non-modern ruling agencies, we need to examine them in their own metaphysical environments, on their own ontological terms.