Late Roman and Migration Period elites from Lithuania – locals or migrants? Reinterpretation of the current concept based on 87Sr/86Sr stable isotope analysis

The archaeological record of the mid-1st millennium AD in Lithuania reveals marked changes in culture and influences from various regions of Europe, which are typically attributed to immigration. To assess the immigration hypothesis and mobility, we carried out ⁸⁷Sr/⁸⁶Sr analysis on human teeth (n = 40) from 11 cemeteries. Samples were selected to evaluate the two supposed directions of immigration as well as mobility, both for individuals of different sexes and between different social groups. Even though 12 (30%) individuals were identified as non-locals, it is impossible to determine whether these individuals originated from other regions in Lithuania or from more distant regions due to the overlap of ⁸⁷Sr/⁸⁶Sr baseline values. However, our results allowed us to dismiss the areas of origin that dominate in the archaeological debates, viz., Southeastern and Central Europe. The majority of non-local individuals were identified in Western and Central Lithuania, indicating that this region was characterised by a different mobility structure than that of Southern and Eastern Lithuania. There were no differences in mobility between males and females or between social groups. The identified mobility patterns most likely reflect established models of social behaviour rather than sudden transformations.