Domnall I of Strathclyde

Dyfnwal
King of Strathclyde
Dyfnwal's title as it appears on 29r of Paris Bibliothèque Nationale MS Latin 4126 (the Poppleton manuscript): "rex Britanniorum".
Successor	Owain ap Dyfnwal
Died	908×915
Issue	probably Owain ap Dyfnwal

Dyfnwal (died 908×915) was King of Strathclyde. Although his parentage is unknown, he was probably a member of the Cumbrian dynasty that is recorded to have ruled the Kingdom of Strathclyde immediately before him. Dyfnwal is attested by only one source, a mediaeval chronicle that places his death between the years 908 and 915.

Dyfnwal's parentage is uncertain. No historical source accords him a patronym. He could have been a son of Rhun ab Arthgal, the last identifiable King of Strathclyde before Dyfnwal. Rhun was a member of the long-reigning Cumbrian dynasty of Strathclyde. He is the last monarch to be named by a pedigree preserved within a collection of tenth-century Welsh genealogical material known as the Harleian genealogies.

A certain son of Rhun was Eochaid (fl. c.880), a man who seems to have possessed a stake in the Scottish kingship before falling from power in the last decades of the ninth century. It is unknown if Eochaid actually ruled the Kingdom of Strathclyde, although it is possible. If Dyfnwal was not a son of Rhun, another possibility is that he descended from Eochaid: either as a son or grandson. Alternately, Dyfnwal could have represented a more distant branch of the same dynasty. If Dyfnwal was indeed a son of the Eochaid, a sister of his could have been Eochaid's apparent daughter, Land, the wife of Niall Glúndub mac Áeda (died 919) attested by the twelfth-century Banshenchas.

Rhun's father, Arthgal ap Dyfnwal (died 872), ruled the Kingdom of Al Clud. In the 870s, the kingdom's principal citadel—the eponymous fortress of Al Clud ("Rock of the Clyde")—fell to the Irish-based Scandinavian kings Amlaíb (fl. c.853–871) and Ímar (died 873). Thereafter, the kingdom's capital seems to have relocated up the River Clyde to the vicinity of Govan and Partick. The relocation is partly exemplified by a shift in royal terminology. Until the fall of Al Clud, for example, the rulers of the realm were styled after the fortress; whereas following the loss of this site, the Kingdom of Al Clud came to be known as the Kingdom of Strathclyde in consequence of its reorientation towards Ystrad Clud (Strathclyde), the valley of the River Clyde.