Tracing the genetic legacy of Altaic-speaking populations suggested long-distance migration and multi-source admixture shape the genomic diversity of Xibe and Daur.

Long-distance migrations across Eurasia have led to extensive admixture among ethnolinguistically diverse Altaic speakers and their Indo-European neighbors; however, the population histories of the Xibe and Daur in northern China remain poorly understood. We address this gap by analyzing genome-wide SNP data from 324 individuals to characterize genetic structure, admixture, and migration. Both groups cluster with East Asian populations, particularly Altaic-speaking groups, consistent with a shared origin of the geographically distinct Xibe and Daur populations. We identify divergent post-migration histories, in which northwestern Chinese Xibe show distinct profiles and stronger genetic ties to the Daur, while northeastern Xibe have substantial contributions from indigenous ancient Northeast Asian (ANA) and Sino-Tibetan speakers. Admixture modeling indicates that Daur and the majority of Xibe populations are best described as two-way mixtures with Han and ANA groups; a distinct West Eurasian/Steppe signal persists in specific Shandong subgroups, reflecting historical trans-Eurasian cultural interactions and gene flow. Notably, Xinjiang Xibe share a high-ANA genetic profile, whereas other Xibe groups possess additional Han-related ancestry. Shared-segment analyses support a northeastern origin for the Xinjiang Xibe, where subsequent westward migration served as a complementary event that preserved this ancestral diversity, whereas the Daur retains strong ties to ANA, especially those from Inner Mongolia. Together, these results clarify the layered demographic histories of Xibe and Daur, refine models of population structure in northern East Asia, and illustrate how repeated movements and regional interactions generate present-day genomic diversity at the crossroads between North China and Siberia.