Owen I of Strathclyde

Owain ap Dyfnwal
King of Strathclyde
Owain's name and title as it appears on page 158 of Cambridge University Library MS Ff.1.27 (Libellus de exordio).
Predecessor	Dyfnwal
Successor	Dyfnwal ab Owain
Issue	Dyfnwal ab Owain
Father	possibly Dyfnwal

Owain ap Dyfnwal (fl. 934) was an early tenth-century King of Strathclyde. He was probably a son of Dyfnwal, King of Strathclyde, who may have been related to previous rulers of the Kingdom of Strathclyde. Originally centred in the valley of the River Clyde, this realm appears to have undergone considerable southward expansion in the ninth or tenth century, after which it increasing came to be known as the Kingdom of Cumbria.

Owain may have represented the Cumbrians in the tripartite alliance with the kingdoms of Alba and Mercia, apparently assembled by Æthelflæd, Lady of the Mercians. Around this time, the Cumbrians are recorded to have campaigned against either Ragnall ua Ímair or Sitric Cáech. Owain may also be the king of Strathclyde who is recorded to have submitted to Æthelflæd's brother, Edward, King of the Anglo-Saxons, in 920 with Ragnall and Custantín mac Áeda, King of Alba. Moreover, Owain seems to have been present at another assembly in 927, when he, Custantín, Ealdred (son of Eadwulf), and perhaps Owain ap Hywel, King of Gwent, acknowledged overlordship of Edward's son and successor, Æthelstan. This assembly may have been held on or near the River Eamont, seemingly the southern frontier of the Cumbrian kingdom.

Owain is first securely attested in 934, when Æthelstan invaded and ravaged the Scottish Kingdom of Alba and seemingly Strathclyde as well. In the aftermath of this campaign, both Owain and Custantín are known to have been present at Æthelstan's royal court, witnessing several charters as subreguli of the Englishman. Three years later, the Scots and Cumbrians allied themselves with Amlaíb mac Gofraid against the English at the Battle of Brunanburh. It is possible that Owain is identical to the unnamed Cumbrian king recorded to have participated in this defeat by the English. If he was indeed present, he could have been amongst the dead. His son Dyfnwal ab Owain is recorded to have ruled as King of Strathclyde within a few years.