The Xibe population originated in northeastern China, but migrated to northwestern China in 1764-6. We have used a combination of published autosomal and Y-chromosomal data, together with newly derived mtDNA HVSI sequences, to investigate the extent to which genetic data can reveal the geographical origin of this population and the level of gene flow after the migration. We find that mtDNA data are uninformative, but that both autosomal and Y-chromosomal data indicate a northeastern origin, and that the Y data suggest 28% subsequent male-mediated gene flow into the population. We thus conclude that an appropriate combination of genetic data and analytical methods can reveal even recent and local events in the history of a population. In the Chinese samples examined, the combination of a northeastern autosomal background with a northwestern Y chromosome is indicative of a Xibe individual.