Debate surrounds the identity of the Europeans who settled Iceland and Greenland in the early medieval period. Historical sources record settlers travelling from Norway to Iceland and then Greenland, but recent analyses of biological data suggest that some settlers had British and Irish ancestry. Here, the authors test these hypotheses with 3D-shape analyses of human crania from Scandinavia, Britain and Ireland, and one of the Norse colonies in Greenland. Results suggest that some 63 per cent of the ancestry of the Greenlandic individuals can be traced to Britain and Ireland and 37 per cent to Scandinavia. These findings add further weight to the idea that the European settlers who colonised Iceland and later Greenland were of mixed ancestry.