This chapter offers new explorations of animal–human relationships, specifically but not limited to the human–horse relationship in Viking Age and medieval Scandinavian evidence. Working between literary and legal texts, as well as mortuary archaeology, it asks a key question of these sources: How did medieval Scandinavians conceive of their relationships with certain animals, especially the horse? Taking a posthumanist perspective, the analysis here suggests that animals could occupy a complicated conceptual and legal space that, while not quite ‘human’, was attributed with its own intricate understanding and expression of personhood. This non-human personhood, when explored in transdisciplinary ways, reveals that, much like humans, animals can be both agent and object in medieval networks and mindscapes, making this fertile ground for further inquiry.