Vortipor is one of the kings denounced by Gildas. His memorial stone has been found in Dyfed. There is also discussion of Vortipor in Molly Miller's  1978 "Date-Guessing and Dyfed" Studia Celtica 12/13: 33-61. Alcock's Arthur's Britain discusses the foundation of Dyfed by the Irish and the Irish genealogy which includes Vortipor. The Irish dynasty of Dyfed took on Romanized names almost from the time they moved to Britain.

The Early British Kingdoms Website has a short biography of this man at: http://freespace.virgin.net/david.ford2/dyfed.html#Vortepor