This issue of Current Archaeology focuses on the results of a very special project – one that has been sought for years because it reveals the relative size, scope, and nature of migration in post-Roman Britain, allowing us to explore such stories at multiple levels. My first attempt to do this was in 2010, working with geneticist Ceiridwen Edwards on a Leverhulme-funded project in which we selected samples from Apple Down, an early Anglo-Saxon cemetery in East Sussex. Alas, our attempts to obtain genetic data were unsuccessful – but in 2016 a collaboration between me, Stephan Schiffels, the Sanger Institute, and Oxford Archaeology East published ten full genome sequences from early medieval individuals from Cambridgeshire. It was thrilling because it used full genome data from which the geneticists were able to distinguish DNA with a continental European source, as well as DNA with a local source, based on differences at an allele level.
As an archaeologist, what was most thought-provoking for me were the results from the early medieval cemetery at Oakington that I excavated between 2010 and 2015 (CA 261). There, we were able to describe several individuals with Continental origins, as well as a local, and one person with a mix of these two ancestries. This kind of insight was amazing, and at the time it seemed like the beginning of an answer to an age-old debate about the nature of early medieval migration, integration, and assimilation. In 2016, this result was a revelation, and ten successfully sequenced samples was huge. That project was an early example of a new way to explore ancient DNA: next-generation sequencing, which has opened up archaeogenetics in a big way – the Bell Beaker project (CA 338) and revelations about Neolithic (CA 384) and Iron Age populations are recent examples.
Ten samples (with four dating to the 5th and 6th centuries), however, was a small body of data from which we made quite big claims. We needed more information, and in 2017 Stephan and I started collecting further samples, first from Oakington, as well as Polhill and Eastry in Kent, then from more Cambridgeshire sites: Hatherdene Close (Cherry Hinton) and Ely. A selection of Continental samples allowed for comparison, and we were now working on one of the largest aDNA projects. Professor David Reich’s team (Harvard University) donated their early medieval sequences to us – these included West Heslerton and, delightfully, the Apple Down samples that Ceiridwen and I had worked on 15 years before. Meanwhile, Joscha Gretzinger, Stephan’s doctoral student, started presenting results at conferences, and samples from further cemeteries were donated to us, including from Lakenheath and Buckland.
Trials and triumphs
Unfortunately, the COVID-19 pandemic prevented us sampling from the upper Thames Valley, but nonetheless all this work took our samples to well over 400, a 40-times increase on the 2016 project and now encompassing sites from the South-west, Kent, East Anglia, and North Yorkshire. Importantly, the increased size allows for meaningful statistical analysis. This means that we have been able to identify the impact of post-Roman migration on the east of England at a national, regional, and an individual level. We have been able to identify generations of people with shared family histories, and have explored the association between ancestry and grave goods. We are very grateful to CA for letting us work on this whole issue, because a single article could not do the breadth of our findings justice. In this issue, John Hines will introduce the question of early Anglo-Saxon migration, while Stephan and Joscha will describe the genetics, and the implications of the results for population history. I will then explore the cemeteries we investigated, and then (alongside Dominic Powlesland and Allison Stewart) we will start to tell the individual stories that we can see in this wealth of data. Because DNA can identify ancestry, but not the act of migration itself, we have also invited Sam Leggett to write about her new isotope data, and to explore how our DNA data intersects with it. Finally, Joanna Story, a historian who is independent of the project, has agreed to draw together all these strands in a concluding article looking at the wider impact of this work.
Even with this extra space, though, to write this issue of Current Archaeology we have focused on only selected aspects of the project – but it can be explored in even more detail in the original paper in Nature (it is also available as an open-access article online; see ‘Further reading’, below). For me, this project was years in the making, and because of its scale and focus it will take a similar time to replicate. Notwithstanding that, we anticipate an explosion of DNA analysis in archaeology, and hope that some of the questions we explore in this issue of Current Archaeology will become routine analytical points. In the meantime, however, what we have done is changed the conversation, from what the size and scope of the early medieval migration was, to what impact the migration had on the archaeological record, on the populations they encountered, and on people at an individual, family, and community level. Archaeogenetics now allows us to explore complex issues like gender, identity, and personhood, armed with information about genetic relationships and ancestry. This is a revolution that opens new windows into the past, and we hope it will not be long before whole cemeteries can be explored in this way.
Further reading Gretzinger, J., Sayer, D., Justeau, P. et al., ‘The Anglo-Saxon migration and the formation of the early English gene pool’, Nature 610: 7930 (2022). Available online at: doi.org/10.1038/s41586-022-05247-2