Abstract
The Late Iron Age in Europe (5th–1st centuries BCE) was marked by profound economic, social, and cultural shifts, including the expansion of trade and interaction networks. These aspects provide a valuable framework for exploring human mobility and its demographic and social implications. This study examines the extent and characteristics of mobility during this period within the core of the La Tène cultural sphere, focusing on present-day Switzerland. Additionally, it explores potential cultural factors shaping mobility patterns.To assess residential mobility, we analyze strontium (⁸⁷Sr/⁸⁶Sr), oxygen (δ¹⁸O), and sulfur (δ³⁴S) isotopic ratios from dental enamel and bone collagen in a sample of human remains (N ⁸⁷Sr/⁸⁶Sr = 101; N δ¹⁸O = 90; N δ³⁴S = 121) from various Swiss sites dating to the last five centuries BCE. These results are interpreted in relation to faunal and environmental baselines and examined for demographic and funerary trends. Results show considerable spatial variation in the frequency of nonlocal individuals, suggesting that both short- and long-distance mobility was influenced by regional political and economic factors. No correlation was observed between mobility and sex, implying that specific residential rules were not systematically applied. Isotopic variability does not correlate with funerary treatment, suggesting that geographic origin played a minor role in social identity compared to factors such as gender, socioeconomic status, and community affiliation. These results contribute to a broader understanding of demographic dynamics in Iron Age Switzerland and underscore the complexities of reconstructing past mobility through isotopic analysis.