Since leaving Africa, human populations have gone through a series of range expansions. While the genomic signatures of these expansions are well detectable on a continental scale, the genomic consequences of small-scale expansions over shorter time spans are more challenging to disentangle. The medieval migration of the Walser people from their homeland in ssouthern Switzerland (Upper Valais) into other regions of the Alps is a good example of such a comparatively recent geographic and demographic expansion in humans. While several studies from the 1980s, based on allozyme markers, assessed levels of isolation and inbreeding in individual Walser communities, they mostly did so by focusing on a single community at a time. Here, we provide a comprehensive overview of genetic diversity and differentiation based on samples from multiple Walser, Walser-homeland, and non-Walser Alpine communities, along with an idealized (simulated) Swiss reference population (Ref-Pop). To explore genetic signals of the Walser migration in the genomes of their descendants, we use a set of forensic autosomal STRs as well as uniparental markers. Estimates of pairwise F