A range of medieval texts associates King Arthur with the island of Sicily. The earliest, Gervase of Tilbury’s Otia Imperialia, recounts how a man followed a runaway horse into the side of Mount Etna and encountered Arthur there. A similar story is told a decade later in Caesarius of Heisterbach’s Dialogus Miraculorum. Sicily also takes on the role of Arthur’s final resting place in Floriant et Florete and is depicted as the enchanted realm of Arthur in Guillem de Torroella’s La Faula. Further brief references from medieval Italy and France seem to also reflect this tradition. To greater or lesser degrees, these texts present the very real and much-visited island of Sicily as proxy for Avalon and as an otherworld realm. On the face of it, Sicily is not an obvious location with which to associate Arthur; the Mediterranean world does not impinge on most of the influential narratives of the Matter of Britain. The precise origins of this tradition are difficult to discern, but it seems to have developed in tandem with a wider interest in Arthurian material in this part of the world. The story Gervase relates is one of a number of responses to the figure of Arthur that emerge in Italy and Sicily at a relatively early stage. Some of the earliest Arthurian imagery comes from the western Mediterranean in the form of twelfth-century artworks at the cathedrals of Otranto (then in the kingdom of Sicily) and Modena. When accounts of Arthur in Sicily are examined, two things become apparent. The first is how far the location, topography and history of Sicily might have suggested points of connection with well-established depictions of otherworld spaces. The second is that a number of these texts seem to engage with the Matter of Britain for political ends. The island of Sicily was a much-contested territory and it changed hands at several points throughout the Middle Ages. The figure of Arthur is used to authorize and critique the claims of a variety of political actors. This potent intersection of otherworld geography and political claims is central to British debates about Arthur’s return from Avalon in the period, but how such associations operated beyond Britain remains under-explored.