What can ancient DNA tell us about migrations into ancient Britain?

This blog was written by Dr Manuel Fernández-Götz (School of History, Classics and Archaeology, University of Edinburgh).

Ancient DNA (aDNA) studies are revolutionising our understanding of the human past, particularly through the identification of migrations in prehistoric times. The interpretation of migratory movements has been heavily debated in archaeology since the 19^th century. While the appearance of new objects or cultural traditions in a region can sometimes point to the arrival of new populations, other alternative explanations such as trade or diffusion of ideas are often also possible. Over the last two decades, the increasing application of bioarchaeological methods, e.g. aDNA analyses, is helping to shed new light on old debates, as well as to uncover hitherto unknown scenarios of large-scale migrations. This is the case with a new study first published in December 2021 in Nature, which suggests the existence of large-scale migratory movements from continental Europe into Britain during the Middle to Late Bronze Age, more specifically in the period from ca. 1300-750 BC. 

This research is part of the large-scale projects undertaken in recent years by the Harvard genetics lab directed by Prof David Reich and his collaborators around the world. In this case, the article brings together over 200 scholars (myself among them), including the team led by Prof Ian Armit from the University of York, who is directing the COMMIOS Project, funded by the European Research Council. In this paper, the authors bring together the results from sequencing the genomes of nearly 800 Bronze and Iron Age individuals from Britain and various parts of the European continent. The results corroborate the existence of significant connectivity across the English Channel in the Middle and Late Bronze Age, including not only the movement of goods, but also people. The most notable outcome of the analyses is that Early European farmer (EEF) ancestry, coming from the continent, increased significantly in England and Wales between 1000 and 875 BC, due to the arrival of migrants during this period and in the immediately preceding centuries. These newcomers seem to have been genetically most similar to individuals from France, although their precise area of origin still needs to be further determined by future studies. 

Although aDNA does not tell us, in itself, what language people spoke, the combination of different strands of evidence (genetics, archaeology, and linguistics) allows for some plausible hypotheses to be established. In this sense, the new results from the Nature article open the possibility that Celtic languages could have been introduced to Britain from the continent as part of these Late Bronze Age population movements. This hypothesis would fit well with the idea of ‘Celtic from the centre’ as proposed in 2020 by Prof Patrick Sims-Williams (Aberystwyth University) on the basis of linguistic and archaeological evidence. According to him, it is likely that early Celtic languages spread from Gaul (mainly present-day France) into Britain in the first millennium BC. 

How was this article covered in the media? The publication has attracted wide media coverage in the UK and abroad, in most cases with a rather adequate representation of the data. The BBC explained the findings accurately while also giving context for its meaning, for example by stating that this migration from France may be how Celtic languages came to Britain. However, with a quote from an expert on aDNA from Trinity College Dublin (Dr Lara Cassidy), the article indicates the findings do not show for certain that this is how Celtic languages arrived in Britain, although it lends evidence to this idea. They included statements from co-authors of the study and independent experts in the field, strengthening the reporting of the research. 

The Daily Mail portrayed the findings largely accurately while also including useful maps, although the term ‘displaced’ used in the headline does not appear in the original article. A positive aspect of the Daily Mail report was the addition of boxes with extra, relevant information (e.g. explaining when the Bronze Age was and the practices associated with this period) to give the reader context for understanding the rest of the piece. This addition is helpful for interested readers with no background in prehistory. Both the BBC and the Daily Mail were clear about how the researchers did not know why this migration took place or where exactly the migrants came from although it was likely from France. 

Why is this research important? Celtic languages are still spoken in various Atlantic regions including Wales, Scotland, and Ireland, and researching their origins is not only relevant from an academic perspective, but also for people for whom the use of a Celtic language continues to represent an important part of their identity. On a broader level, aDNA corroborates that the history of humankind is one of migrations, since its very beginnings to the present, and that Britain is no exception to this. Looking at population movements and their impact from a ‘deep history’ perspective can contribute to a better understanding of present-day migrations and counteract isolationist narratives. People have always moved and mixed, to various degrees, and will continue to do so in the future. We are, very much, Homo migrans.