Cabuniaeginus is an indigenous god of the southern Cantabri, attested on a Roman-period altar recovered from the wall of the hillfort of Monte Cildá above Olleros de Pisuerga (Palencia). The dedicant, Doiderus of the Tridiavi, set up the stone for the health of Duratus of the Polecenses, showing the god invoked as a personal protector and healer within local kin-group religion. The theonym is otherwise unknown: Blázquez sought Indo-European parallels in dedications such as Devaco Caburio from the Meseta, Ángel Montenegro derived the root from pre-Indo-European toponyms of the Cantabrian mountains (Cabuérniga, Caborana), and Karl Horst Schmidt argued for a Celtic origin. The altar is displayed in the Museum of Prehistory and Archaeology of Cantabria in Santander.