Triffyn ap Rhain

Triffyn son of Rhain (Welsh: Triffyn ap Rhain; died c. 814) was an 8th- and 9th-century king of Dyfed.

He was the son of Rhain ap Maredudd. On the death of his father, Triffyn did not succeed him—instead, his uncle Owain did. After Triffyn succeeded Owain, nothing is known about the realm of Dyfed before Hyfaidd went to Alfred the Great in the 880s to request help opposing Rhodri the Great's younger son Cadell. It's possible the kingdom—crushed by Coenwulf of Mercia around 818—fell under the control of the Vikings.