First anthropology became unbound from “the village”, then from the single site, and gradually from the physical site altogether. As humans resume their push into space, anthropology is set to become unbound from the earth itself. This essay considers what the discipline has offered and can offer toward understanding the present and future of space colonization. It begins by examining the surprisingly long and productive history of anthropology’s engagement with the subject, going back at least to the 1950s. Then it surveys current analysis of law, sovereignty, and nationalism in space, which largely imagines law and identity in off-earth settlements as more-or-less direct extensions or transfers of earth law and identity; in other words, space settlers will remain affiliated with and loyal to their source countries (or companies). However, taking seriously the analogy of terran migration and colonialism, where colonies developed distinct and separatist identities, the essay predicts the emergence of exonationalism, in which over generations colonists will invent new identities and shift their affiliations to their non-terran homes and ultimately seek independence from the earth. The essay concludes with reflections on how the settlement of space, still a distant goal, will reshape our definition of the human and therefore the practice of anthropology as the science of human diversity.