Mission impossible? Quantifying aquatic resource consumption in historic period Estonia (AD 1100‒1800)

Abstract Sulfur stable isotope ratios (δ 34 S) have become increasingly common in archaeology for studying paleodiet, especially in occasions where there is a need to identify aquatic resource consumption more accurately. This is particularly relevant in the Baltic Sea region, where brackish conditions tend to mask “typical” marine carbon isotopic signals. Here we report new δ 34 S values for 126 human bone collagen samples which will be analyzed together with previously published data to investigate the potential of sulfur isotopes as an alternative proxy for aquatic resource consumption in historic period Estonia (ca. AD 1100‒1800). Bayesian statistical programming was used to provide quantitative dietary estimates, suggesting that the diet of the general population was predominantly terrestrial. The inclusion of δ 34 S as an additional dietary proxy produced generally comparable model results to the scenario that excluded δ 34 S. A sub-selection of samples was also radiocarbon dated and calibrated to take into account potential reservoir effects. For burials of commoners, the average contribution of 10% fish to dietary carbon does not significantly alter calibrated date ranges, even in the occasion where data on local reservoir effects is insufficient. This study has demonstrated both the potential and the pitfalls of using δ 34 S in this temporo-spatial context, and the new stable isotope and 14 C data have shed light onto individual site-histories but also to broader cultural processes and changes that occurred during these turbulent times in this region.