An investigation of diet in early Anglo-Saxon England using carbon and nitrogen stable isotope analysis of human bone collagen

Abstract

The principal aim of this work is to investigate whether protein sources in human diets in early Anglo-Saxon (5th–7th century AD) England varied with geographic location, or with respect to age or sex. The methodology used was analysis of δ15N and δ13C in human bone collagen from 76 adult skeletons from a total of 18 different cemeteries located in inland, riverine and coastal environments. In order to control for the possible effects of socio-economic status on diet, only high status individuals, as identified by grave goods, were studied. Data were analysed using statistical manipulation of the raw results and using IsoSource (Phillips and Gregg, 2003), a mathematical treatment which models the composition of the protein part of human diets using bone stable isotope ratios when the isotopic values for potential protein sources are known or can reasonably be inferred. The results suggest that protein sources varied little according to geographic location and that terrestrial foods dominated at all locations. However there were some subtle patterns. Slightly elevated δ13C in skeletons from coastal locations, and δ15N in those from riverine sites may indicate that communities in these locations made greater use of marine and freshwater resources respectively. If this is correct then it demonstrates that 5th–7th century communities made some use of wild resources even within a predominantly agrarian economy. In general the analysis of the raw data and the IsoSource results were mutually supportive, and this work demonstrates the value of this twin-pronged approach to analysis of human bone stable isotope data.