Little is known of this local warrior prince who usurped the throne of Ergyng upon the death of King Cynfyn, around AD 615. He is said to have fought against the Saxons (presumably the Mercians) and to have granted land on the Wye, at Bolgros, to Bishop Ufelfyw of Ergyng in thanksgiving for his victories. He also appears in a number of charters listed in the Book of Llandaff, which Dr Wendy Davies takes to be genuine and dates to c.AD 615-19.
This character is not found using the epithet, the Old, but, nevertheless, should probably be identified with Gwrfoddw Hen. He was the son of Amlawdd Wledig and maternal uncle of High-King Arthur, who may have supported him in taking Ergyng. He supposedly died on a wild boar hunt in Brittany. Gwrfoddw had a son named Erfig, but he did not succeed to the throne of Ergyng which was quickly re-taken by King Cynfyn's son, Gwrgan Fawr.