First Ever Insular Celtic Dictionary Being Written

By Owain Williams

Academics at Aberystwyth University in Wales are writing the very first dictionary of ancient Insular Celtic — that is, the Celtic languages spoken in Britain and Ireland. The dictionary will draw on both place names and personal names recorded in Greco-Roman texts and on inscriptions dated up to AD 500.

The project leader, Dr Simon Rodway, Senior Lecturer in the Department of Welsh and Celtic Studies, said “These disparate sources have never before been brought together in a way that offers such a comprehensive insight into the nature of Celtic languages spoken in these islands at the dawn of the historical period.”

In addition to studying ancient Insular Celtic languages, it is hoped that the project will shed some light on pre-Celtic languages of Britain and Ireland. According to Dr Rodway, “While it is certain that non-Celtic languages were spoken in these islands before the Celtic languages, and for some time alongside them, we have no uncontroversial direct evidence for those languages, and hypotheses about them range from the cautious to the fanciful. A full collection of the available evidence will allow us to sort the wheat from the chaff.”

The notion of calling the languages noted in this dictionary Celtic may irk some. The Celtic identity of the ancient inhabitants of Britain and Ireland has been a point of contention for decades. Some scholars argue that, because the language spoken in Britain and Ireland is connected to the languages spoken throughout Europe, from the Iberian Peninsula to the Balkans and even in Anatolia, by people identified as Celts, then the prehistoric inhabitants of Britain and Ireland were Celtic. On the other hand, other scholars — known as Celtosceptics — have argued that, because the peoples of Britain and Ireland did not refer to themselves as Celts, then we should not do so either. One problem with the Celtosceptic argument is that, as John Koch writes, “since the people of Iron Age Britain and Ireland have left us only fragmentary written records, we do not know with absolute certainty ... that they did not identify themselves as Celts” (2003, p. 43). In fact, it has recently been pointed out that Pytheas of Massilia, a Greek explorer of the fourth century BC, did refer to the inhabitants of Iron Age Britain as Keltoi or Celts. The crux of the matter is a passage from Strabo, who notes how Hipparchus claimed — based on the work of Pytheas — that the inhabitants of the British Isles (not Ireland) were Celts; in his Geography, Strabo disagrees with Hipparchus, instead calling the people Britons (2.1.18). According to Patrick Simms-Williams, the reason why later Roman-era authors, beginning with Julius Ceasar, refer to the inhabitants of the Britain as Britons and not as Celts is because “Caesar had strong reasons for not wanting his supporters to regard Britain, which he failed to conquer, as part of Keltike, which he conquered in its entirety” (2025, p. 449). Subsequent authors simply followed suit.

References:

Koch, J. “Celts, Britons, and Gaels—Names, Peoples, and Identities.” Transactions of the Honourable Society of Cymmrodorion 9 (2003), pp. 41–56.

Simms-Williams, P. “‘Celtic Britain’ in Pre-Roman Archaeology, Reconsidered.” Oxford Journal of Archaeology 44 (2025), pp. 446–461.