Piecing Together the Past: Challenging the Traditional Views of Early Medieval Humans in Britain One Isotopic Life History at a Time

The early medieval era in Britain (c. late 4th to 8th centuries AD) is often characterised as an enigmatic period that witnessed significant human migration from places beyond Britain. Throughout these centuries a variety of evidence also points to local and cross-regional mobility, linked to factors such as seasonality, subsistence strategies, climate, and conflict. This study investigates the extent of mobility of early medieval individuals via multi-isotope analysis. Specifically, this study conducted bulk bone collagen carbon, nitrogen, and sulfur isotope analysis, incremental tooth dentine collagen carbon, nitrogen, and sulfur isotope analysis, and tooth enamel strontium, oxygen, and carbon isotope analysis, and has pioneered the use of the sulfur isotope system as an incremental marker of intra-individual mobility. This study has scrutinised the sulfur isotope data in relation to the other isotope systems to further our understanding of the sulfur isotope system. Isotope analyses were undertaken on skeletons from three cemeteries dating largely between the 5th and 7th centuries AD. The sites included Yatton, North Somerset, in the southwest of England, Sewerby, Bridlington, East Yorkshire, and Andrew’s Hill, County Durham, both in the northeast of England. These analyses and the results from them make a significant contribution to the current corpus of early medieval human isotope data from southwest and northeast England, especially regarding the incremental tooth dentine sulfur isotope profiles which are generally rare in published literature and contribute important information on intra-individual mobility in early medieval populations. The tooth enamel strontium and oxygen isotope data and the bone and dentine collagen sulfur isotope data revealed that the majority of individuals analysed in this project were non-local to their burial sites. The incremental tooth dentine collagen sulfur isotope profiles of the majority of individuals studied in this project revealed evidence of intra-individual mobility throughout their childhood and early adulthood.