This family tree is based on the majority Kurgan Theory of the origin of Proto-Indo-European in the steppes of eastern Europe (present-day Ukraine and Russia), as one aspect of the more mobile and more open cultures that developed around the first taming of horses and the invention of the wheel.

All time periods shown in the family tree are tentative. The separation of Germanic is shown according to the opinion of Don Ringe in From Proto-Indo-European to Proto-Germanic (second edition 2017). David Anthony thinks it occurred earlier, in association with the development of the Corded Ware culture between the Dniester and the Vistula: The Horse, the Wheel and Language (2007). Anthony's work is in any case a convincing refutation of the late 20th century idea (Colin Renfrew) that the Indo-European language family originally spread out of Anatolia.

The family tree postulates a Proto-Celto-Italic language that emerged in the third millennium BCE, probably in the middle Danube valley, perhaps associated with a spread of the Yamnaya culture from the Pontic Steppe towards the Pannonian Basin. It then divided into more northerly Proto-Celtic and more southerly Proto-Italic (the ancestor of Latin, which eventually became the modern Romance languages: Italian, Spanish, etc). But this is only one hypothesis. It is also possible that Celtic and Italic were always distinct, merely sharing certain features because of close geographical proximity.

There are several theories of when Celtic speakers arrived in the British Isles and how the 'Insular Celtic Languages' evolved. Scholarship increasingly supports an arrival in the second or even the late third millennium, much earlier than was previously supposed. Archaeologists have demonstrated a significant cultural movement out of the Iberian Peninsula. It has been eye-catchingly proposed that Celtic speakers were involved from the outset ('Celtic from the West'), but the linguistic arguments are very weak. The new culture could well have become associated with Celtic dialects as it spread north and east through the territory of modern France and the Low Countries, from where it crossed to Britain.

It is now agreed the split into Goidelic and Brythonic languages occurred after the arrival of Celtic in the British Isles. Goidelic (modern Irish, Scottish Gaelic, Manx) and Brythonic (modern Welsh, Cornish, Breton) are distinguished by their different treatments of the kw sound inherited from Proto-Indo European: this became k in Goidelic (spelled in the modern languages) but p in Brythonic. However, the Verb Subject word-order found in all Insular Celtic, but not in the Celtic of continental Europe, suggests there was a time when Insular Celtic was more-or-less a single tongue.

Simplified Family Tree of Cornish

© 2024 Ian Jackson