Bronze Age migration may have brought Celtic languages to Britain

The largest analysis of ancient DNA to date has revealed a mass migration of people from what is now France into England and Wales during the late Bronze Age, which may have spread Celtic languages to Britain.

Two large migrations of people into Britain were previously known, the first taking place around 6000 years ago. The ancestry of these people came mostly from a group known to archaeogeneticists as Early European Farmers, with around 20 per cent from another group called Western European Hunter-Gatherers. This migration led to the replacement of most of the existing local hunter-gatherer ancestry.

Around 4500 years ago, at the start of the Bronze Age, there was a second migration that consisted of descendents of livestock farmers from the Pontic-Caspian steppe – grassland that spans from present-day Bulgaria to Kazakhstan. Ancestry from this group eventually formed at least 90 per cent of the genetic make-up in Scotland, England and Wales.

People living in England and Wales today have more ancestry from Early European Farmers than people in the early Bronze Age did, suggesting a third migration from Europe may have occurred more recently.

Ian Armit at the University of York in the UK and his colleagues sequenced the genomes of nearly 800 individuals from the Bronze Age to the Iron Age whose remains were found at archaeological sites in Britain and in western and central Europe. They looked at the proportion of Early European Farmer ancestry in these ancient people over time.

The team found evidence of a third mass migration into Britain from France that took place between 1000 BC and 875 BC, during which Early European Farmer ancestry increased from around 30 per cent to roughly 36 per cent on average in southern Britain by the late Bronze Age. In the Iron Age, this stabilised at nearly half of the ancestry in populations of England and Wales.

“We’ve always known this period of the middle and late Bronze Age was a period of tremendous connectivity between Britain and central and western Europe,” says Armit.

“Prior to this study, we would have thought of the movement in terms of individuals and small groups, traders and [people looking for metal]. But the results show society was far more mobile than we thought – large sectors of society were on the move. Societies were very interconnected across the English Channel in a manner we hadn’t really appreciated before,” he says.

The findings help shed light on a debate about when Celtic languages were first spoken in Britain. “The most established theory, based on the analysis of ancient object styles, is that Celtic languages came in during the Iron Age with Celtic speakers from continental Europe,” says Armit.

But the new evidence supports a competing idea, based on linguistic studies, that Celtic languages expanded into Britain earlier, in the middle to late Bronze Age. However, we can’t tell from someone’s DNA what language they spoke, says Armit.

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