Tracing 600 years of long-distance Atlantic cod trade in medieval and post-medieval Oslo using stable isotopes and ancient DNA.

Marine resources have been important for the survival and economic development of coastal human communities across northern Europe for millennia. Knowledge of the origin of such historic resources can provide key insights into fishing practices and the spatial extent of trade networks. Here, we combine ancient DNA and stable isotopes (δC, δN, non-exchangeable δH and δS) to investigate the geographical origin of archaeological cod remains in Oslo from the eleventh to seventeenth centuries CE.