This essay attempts to bring into conversation two unlikely bodies of writing. One of these bodies of writing dates from the Middle Ages and might loosely described as medieval travel writing. This literature has been the subject of much recent study, because it addresses one of the first sustained engagements of the West and the East. The other body of writing emerges from recent political thought, in which the responsibilities of individuals and states to those beyond their borders have been debated. These debates, involving themes of cosmopolitanism and sovereignty, turn out actually to emerge from speculations put forth in the 1970s that we are entering a New Middle Ages. In tracing these themes, I hope to contribute to some recent thinking about periodisation, authority and subjection (Davis).