The Epidii (Greek Επίδιοι) were a people of ancient Britain, known from a mention of them by the geographer Ptolemy c. 150. They inhabited the modern-day regions of Argyll and Kintyre, as well as the islands of Islay and Jura.
Some authorities suggest they were Goidelic-speaking rather than Brythonic-speaking as the reported name suggests. The area they are presumed to have controlled later became the heartland of the kingdom of Dál Riata.
Ptolemy does not list a Πολις for the Epidii, but the Ravenna Cosmography (RC 108.4) lists Rauatonium, assumed to be Southend, Kintyre.
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- Campbell, Ewan, "Were the Scots Irish ?" in Antiquity, 75 (2001), pp. 285–292.
- Delamarre, X., Dictionnaire de la Langue Gauloise (2nd ed.). Paris: Editions Errance, 2003. ISBN 2-87772-237-6
- Foster, Sally M., Picts, Gaels, and Scots (2nd ed.) London: B.T. Batsford/Historic Scotland, 2005. ISBN 0-7134-8874-3
- Ptolemy (150), Thayer, Bill, ed., Geographia, Book 2, Chapter 2: Albion island of Britannia, LacusCurtius website at the University of Chicago (published 2008), retrieved 2008-04-26
- The British Section of the Ravenna Cosmography in Archaeologia 93 (1949), 108.4
- The circumnavigation of Scotland compares Ptolemy and the Ravenna Cosmography for the south west coast of Scotland