family and companions from the pre-Galfridian Welsh tradition, including Kaius (Cei), Beduerus (Bedwyr), Guenhuuara (Gwenhwyfar), Uther (Uthyr) and perhaps also Caliburnus (Caledfwlch), the latter becoming Excalibur in subsequent Arthurian tales. However, while names, key events and titles may have been borrowed, Brynley Roberts has argued that "the Arthurian section is Geoffrey’s