Jonas, King of Domnonée
(c.AD 500-540)
(Welsh: Ionas; Latin: Iohannes; English: Jonah)

Jonas appears to have been the son of King Riwal of Domnonée rather than the more traditional Riatham who is well recorded as a much earlier monarch. It was during Jones' early 6th century reign, that Domnonée fell victim to the uncontrollable greed of King Conomor alias Mark of Kernow & Poher. Under the guise of friendship, Conomor managed to both murder poor Jonas and marry his pretty young widow, the daughter of King Budic II of Brittany. His son, Judwal, eventually managed to reclaim the throne.

He is probably to be identified with Iona, King of France as mentioned in the Arthurian story of 'Culhwch and Olwen' attached to the Mabinogion.