Edeirnion, Denbighshire Genealogy
Edeirnion (formerly Edeyrnion) is an ancient cantref in the upper Dee valley in Wales.
The area is said to take its name from Edern (Latin:Eternus), one of the sons of Cunedda, the King of Cumbria. Edern and his brother Meirion had settled in this part of Wales around the year 420.
Traditionally Edeirnion was part of the Kingdom of Powys but was often subject to border disputes with the neighbouring Kingdom of Gwynedd. The area was annexed by Gwynedd during the reign of Llywelyn Fawr but returned to Powys after his death in 1240. It was again occupied by Gwynedd after 1267 before being returned once again to Powys. These frequent border disputes caused a great deal of friction between the two Welsh kingdoms and distracted both from their war against England.
The most famous son of Edeirnion was Owain Glyndŵr (Owain ap Gruffudd Fychan), Lord of Glyndyfrdwy and a descendant of the rulers of Powys through his father Gruffydd Fychan II. In September 1400, Glyndŵr instigated the Welsh revolt against the rule of Henry IV of England and was proclaimed Prince of Wales at Glyndyfrdwy.
In 1974, following the re-organisation of local government in Wales, Edeirnion became part of the district of Glyndŵr in the newly formed County of Clwyd. In 1996, following further re-organisation, Edeirnion became part of the re-created Denbighshire.