Ancient skulls show Anglo-Saxon identity cultural, not genetic
Scholars have long been fascinated by the Anglo-Saxon period of British history, which spans approximately 600 years, from the end of Roman rule in around AD 410 to the start of the Norman conquest in 1066.
Because very few contemporary documents are available, a number of important questions about the early part of the period remain unanswered. One of these is: “Who were the Anglo-Saxons?”
There is general agreement that their origins can be traced to a migration of Germanicspeaking people from mainland northwest Europe that began in the early fifth century.
CONFLICTING EVIDENCE
Uncertainty persists because two of the main lines of evidence contradict each other. Historical documents such as Gildas’ The Ruin of Britain, Bede’s The Ecclesiastical History of the English People and The Anglo-Saxon Chronicle suggest not only that the incomers were numerous, but also that they more or less completely replaced the Romano-British, killing some and pushing the rest to the peripheries.
This picture is not supported by the results of isotopic analyses. Isotopic analysis can help determine where an individual grew up.
When isotopes of strontium and oxygen extracted from Anglo-Saxon skeletons have been compared, they have pointed to only a few of the individuals having grown up in mainland Europe. This has been interpreted as evidence that the Romano-British were not replaced. Rather, they adopted a new language and set of values, beliefs and cultural practices from a relatively small number of incomers.
NEW EVIDENCE
Recently, the authors published a new line of evidence was used to investigate the issue: the three-dimensional (3D) shape of the base of the skull, which bioarchaeologists usually call the cranial base or basicranium.
Previous research has shown that when the basicranium is analysed in 3D, its shape can be used to track relationships among human populations in a similar way to DNA. We reasoned that collecting such data from AngloSaxon skulls and comparing them to similar data from the two potential source regions might shed light on the composition of the Anglo-Saxon population.
MIXED ANCESTRY
Once we had collected the data, a set of statistical techniques called geometric morphometrics (GM) was used to identify similarities and differences in shape among the four groups: Early AngloSaxons, Middle Anglo-Saxons, Pre-Medieval British and PreMedieval Danish.
Developed in the 1980s, GM has long been an important tool in the study of human evolution, but has only recently been embraced by bioarchaeologists. GM allows patterns of shap
The results suggested a substantial difference between the Early Anglo-Saxon Period sample and the Middle AngloSaxon Period. Between 66 and 75 per cent of the Early AngloSaxon individuals were of mainland European ancestry, while 25 to 30 per cent were of local ancestry. In contrast, 50 to 70 per cent of the Middle Anglo-Saxon Period individuals were of local ancestry, while 30 to 50 per cent were of mainland European ancestry.
We think these discrepancies can be explained relatively easily. While strontium and oxygen isotopes are informative about where an individual grew up, they don’t tell us about a person’s ancestry. Hence, it is feasible that some, if not all, of the individuals with local isotopic signatures were second-generation immigrants — that is, their parents originated in mainland Europe but they themselves were born and raised in the British Isles.
LANGUAGE AND CULTURE, NOT GENETICS
There are several potential explanations for the change in composition of the AngloSaxon population between the Early Anglo-Saxon Period and the Middle Anglo-Saxon Period, but we think the most likely is that there was an increase in the number of local people adopting an AngloSaxon identity through time.
This could have been because being Anglo-Saxon was perceived as higher status than being Romano-British. Alternatively, it could simply have been a consequence of people randomly copying one another.
Regardless of the cause of the change in composition, it is clear from our results that being an Anglo-Saxon was more a matter of language and culture than genetics.
Interestingly, this echoes results obtained in the largest ancient DNA study of Vikings published to date. In this study, a number of individuals who were buried as Vikings were found to be of local ancestry, which suggests that being a Viking was also a linguistic and cultural phenomenon rather than a genetic one.
The Anglo-Saxons and Vikings are often viewed in racial terms, with common biological descent deemed to be a key aspect of both groups. However, the results of our study and the Viking DNA one indicate that shared descent was not a requirement for membership of either group.
Instead, it appears that the Anglo-Saxons were a group of individuals of diverse ancestries who shared a common language and culture. The same holds for the Vikings. The Anglo-Saxons and Vikings were, in other words, strikingly similar to the multiracial societies of contemporary northern Europe.
First published in The Conversation. Author Mark Collard is the Canada Research Chair in Human Evolutionary Studies and professor of archaeology, Simon Fraser University; Keith Dobney is chair professor, archaeology, University of Sydney; and Kimberly Plomp is a postdoctoral researcher, Human Evolutionary Studies, Simon Fraser University.