The recently concluded ‘People of the British Isles’ project (hereafter
PoBI) combined large-scale, local DNA sampling with innovative data analysis
to generate a survey of the genetic structure of Britain in unprecedented
detail; the results were presented by Leslie and colleagues in 2015.
Comparing clusters of genetic variation within Britain with DNA samples from
Continental Europe, the study elucidated past immigration events via the
identification and dating of historic admixture episodes (the interbreeding
of two or more different population groups). Among its results, the study
found “no clear genetic evidence of the Danish Viking occupation and control
of a large part of England, either in separate UK clusters in that region,
or in estimated ancestry profiles”, therefore positing “a relatively limited
input of DNA from the Danish Vikings”, with ‘Danish Vikings’ defined in the
study, and thus in this article, as peoples migrating from Denmark to
eastern England in the late ninth and early tenth centuries (Leslie
et al.2015: 313). Here, we consider the
details of certain assumptions that were made in the study, and offer an
alternative interpretation to the above conclusion. We also comment on the
substantial archaeological and linguistic evidence for a large-scale Danish
Viking presence in England.