In this chapter, I develop an alternative framework for a critical theory of international law. Critical theorists have previously attempted to develop a theory of international law which began from the concern that the development of international law has led to the fragmentation of the international legal order. Inspired by the Habermasian view that legitimate law emerged, as a historical phenomenon, alongside the rationalization of the state, critical theorists have been reluctant to theorize the conditions of legitimacy of a global order where constitutionalization and democracy do not obtain. They have instead argued for constitutionalization as a means of assuring international law’s legitimacy. I argue that a critical theory of international law should not depend on the existence of a constitutional order, but could instead begin from a fragmented legal order and involve means of legitimation separate from those normally invoked to explain the legitimacy of the nation-state.