Stable isotopes in an unstable time: understanding diet and social organization at Plinkaigalis, Lithuania

The Late Roman – Migration period (3rd–6th century CE) represents a time of significant, but understudied, sociopolitical change in Lithuania. While general dietary and cultural trends have been identified, more regionally specific data are needed. The focus of this research is to understand the lived experiences of individuals interred in the Late Roman – Migration period cemetery at Plinkaigalis, Lithuania based on isotopic assessments of diet. Analyses included assessments of stable carbon and nitrogen isotopes for bone and dental tissues of 192 individuals and 17 fauna. A MANOVA (Multivariate Analysis of Variance) was utilized to quantify dietary differences. The stable isotope analyses indicate a homogenous C 3 based diet (bone δ 13 C coll ranging from −21.6‰ to –19.8‰, bone δ 15 N Coll ranging from 7.5‰ to 9.5‰, dentin δ 13 C coll ranging from −22.1‰ to −18.9‰, dentin δ 15 N Coll ranging from 8.0‰ to 10.6‰) was present with insignificant variations across age, sex, and status groupings barring slight differences in male/female stable nitrogen and carbon isotope values when sex and age are considered simultaneously. Comparisons to contemporaneous Lithuanian sites and faunal data indicate a homogenous terrestrial diet was present across Lithuania with variations in freshwater fish consumption. In terms of lived experience, this suggests a strong degree of social cohesion and stability in Lithuanian dietary practices during a time of sociopolitical change. The consumption of fish/fishing and access to major waterways is suggested to indicate power centers and elite status. These findings necessitate further investigation of dietary protein intake, waterways, and status.