There has been a persistent misunderstanding of the nature of cosmopolitanism in Immanuel Kant’s 1795 essay “Perpetual Peace,” viewing it as a qualitative break from the bellicose natural law tradition preceding it. This misunderstanding is in part due to Kant’s explicitly critical comments about colonialism as well as his attempt to rhetorically distance his cosmopolitanism from traditional natural law theory. In this paper, I argue that the necessary foundation for Kant’s cosmopolitan subjectivity and right was forged in the experience of European colonialism and the (pre-Kantian) theory it engendered. It is in this context that we witness the universalization of subjectivity and the subjectivization of right, emerging from the justificatory needs of extra-national jurisdiction and resource appropriation. This form of cosmopolitanism, whose emergence necessarily tracks the rise of global capitalism, continues to exert great and often uncritical influence on theories and practices of peace today.