King Dugal

Dubhghall mac Ruaidhrí
King of Argyll and the Isles
Dubhghall's name and title ("King of Argyll") as it appears on folio 19v of Royal Irish Academy MS C iii 1 (the Annals of Connacht).
Died	1268 possibly Norway
Issue	Eiríkr Donnchadh daughter (name unknown)
House	Clann Ruaidhrí (Clann Somhairle)
Father	Ruaidhrí mac Raghnaill

Dubhghall mac Ruaidhrí (died 1268) was a leading figure in the thirteenth-century Kingdom of the Isles. He was a son of Ruaidhrí mac Raghnaill, and thus a member of Clann Ruaidhrí.

Dubhghall was active in Ireland, and is recorded to have conducted military operations against the English in Connacht. In 1259, the year after his victory over the English Sheriff of Connacht, Dubhghall's daughter was married to Aodh na nGall Ó Conchobhair, son of the reigning King of Connacht. This woman's consisted of a host of gallowglass warriors commanded by Dubhghall's brother, Ailéan. This record appears to be the earliest notice of such soldiers in surviving sources. The epithet borne by Dubhghall's son-in-law—na nGall—can be taken to mean "of the Hebrideans", and appears to refer to the Hebridean military support that contributed to his success against the English.

The careers of Dubhghall and his Clann Somhairle kinsman, Eóghan Mac Dubhghaill, exemplify the difficulties faced by the leading Norse–Gaelic lords in the Isles and along western seaboard of Scotland. In theory, these regions formed part of the greater Norwegian commonwealth. However, during the tenures of Dubhghall and Eóghan, successive thirteenth-century Scottish kings succeeded in extending their own authority into these Norse-Gaelic regions. Whilst Eóghan eventually submitted to the Scots, Dubhghall steadfastly supported the Norwegian cause. Recognised as a king by the reigning Hákon Hákonarson, King of Norway, Dubhghall was one of the leading figures in the failed 1263 campaign against the Scots. Although Dubhghall is last recorded resisting the encroachment of Scottish overlordship, the Scots succeeded in wrenching control of the Isles from the Norwegians in 1266. Dubhghall may have died in exile in Norway, where his son, Eiríkr, was an active baron.