Dubgall mac Somairle (Modern Dubhghall mac Somhairle; Anglicized: "Dugald" or "Dougal, Somerled's son") was a 12th-century Scottish nobleman. The son of Somairle mac Gille Brigte, regulus of Argyll, Dubgall is the eponymous progenitor of Clan MacDougall (Clann Dubhghaill, literally "Children of Dougal" or "Dubgall").
According to the Chronicle of Mann, in 1155 he accompanied his father Somairle in an expedition against Guðrøðr Óláfsson, King of the Isles. In 1175, he was one of the Scottish magnates accompanying William I, King of Scotland to York, as William was required to swear fealty to Henry II, King of England. In the same year, he and his chaplain Stephan made a pilgrimage to St Cuthbert at Durham, donating two gold rings to the Cathedral Priory. The Chronicle of Mann alleged that the men of the Isles chose Dubgall to be their king, but this may have been a later concoction, and Dubgall is never given a title in any contemporary source. It has been suggested that he was the founder of the bishopric of Argyll, though more likely this took place under his brother Ragnall mac Somairle.
It is not known when Dubgall died. He is not mentioned again after 1175, but may have lived long afterwards, perhaps even into the 13th century. He appears to have had the following sons,
The last is uncertain. Gille Esbuig appears in Hákonar saga Hákonarsonar, which renders his name "Uspak", as a son of Dubgall upon whom is conferred the royal name Haakon; "Uspak" enjoyed a successful career, but it is not entirely certain that the Dubgall referred as his father is Dubgall mac Somairle.