Ten Viking Age individuals from the northern Norwegian site at Flakstad were analysed for δ13C, δ15N and ancient mitochondrial DNA fragments. The material derives from both single and multiple burials with individuals treated in different ways. The genetic analyses show that the individuals buried together were unlikely to be maternally related, and stable isotope analyses suggest different strata of society. It is, therefore, suggested that slaves may have been offered as grave gifts at Flakstad. A comparison with the remaining population from single graves shows that the presumed slaves had a diet similar to that of the common population, whereas the high status individuals in multiple graves had a diet different from both slaves and the common population. The results provide an insight into the subsistence of different social groups in a Viking Age society, exposing unexpected patterns of living conditions and food distribution.