TREVOR. The Welsh heralds derive the Trevors from Rourd Wiedick, fatlier of Eignian Yothe, which Eignian held the lands of Gaercinion in Powysland, and was grandfather to Kariodoc, Earl of Hereford, early in the sixth century. The first who bore this name was the famous Tudor Trevor, Earl of Hereford, Kariodoc's grandson. Surnames were not hereditary in Wales before the reign of Henry VIII., this being the single exception that I have observed. The first person who adopted Trevor as a settled family name, was John ap Edward ap David, who died in 1494. None of his immediate ancestors had borne the baptismal name of Trevor; and it is therefore likely that he adopted it from the most illustrious of his ancestors, the renowned Earl of Hereford. The great

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.