Dál Riata (also Dalriada or Dalriata) was a Gaelic overkingdom on the western coast of Scotland with some territory on the northern coasts of Ireland. In the late 6th and early 7th century it encompassed roughly what is now Argyll and Bute and Lochaber in Scotland and also County Antrim in Ireland.

Dál Riata is commonly viewed as having been an Irish Gaelic colony in Scotland, although some archaeologists have recently argued against this. The inhabitants of Dál Riata are often referred to as Scots.

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