Integrated osteological and genomic analysis of two individuals from the Ordos Plateau during the Song–Yuan transition

• Integrative bioarchaeology reveals the complex demography of a Song-Yuan frontier fortress. • Genomic evidence reveals significant steppe ancestry, reflecting historical regime shifts. • Skeletal evidence of nutritional stress and reduced stature reveals chronic hardship in females. Two female remains, recovered from water wells at the strategic Yangjiacheng fortress on the Ordos Plateau, were identified as victims hastily abandoned during the intense sociopolitical upheaval of the Song–Yuan transition. This unique depositional context provides a rare window into the historical trajectory of northern steppe populations migrating into the region during this turbulent period. To reconstruct their life histories and the circumstances of their death, this study integrates osteological, isotopic, and genomic analyses. Osteological and paleopathological assessments reveal that both women experienced stunted growth and chronic physiological stress, pointing to a life of hardship and potential social marginalization. Stable isotope analysis indicates a diet dominated by C 4 crops with significant animal protein intake, consistent with the region’s mixed agro-pastoral economy. Genomic sequencing further reveals that while unrelated, both individuals harbored varying degrees of genetic admixture from the Mongolian Plateau, distinguishing them from the genetically homogeneous populations of the Central Plains. Through this rare bioarchaeological lens, the study vividly illustrates the survival conditions, health status, and demographic integration of frontier populations—particularly vulnerable females—during a period of historical transition and warfare.