The use of genetic markers to track colonisation history of mammal species is largely applied to natural colonisations, such as the end glacial colonisations of previously ice-covered areas in northern latitudes. However, it is also possible to use genetic markers to track colonisations of mammal species inadvertently transported as stowaways on boats, such as house mice (Mus musculus). Those mammalian colonisations obviously reflect historical movements of people. Therefore, if comparisons of mice from possible source areas are made with mice from places colonised, any similarity reflects historical movement of people between those two areas. Vikings transported foodstuffs and livestock around the periphery of Europe and mice were able to exploit those resources. There is a remarkable correspondence between mitochondrial lineages of house mice and areas of occupation by Vikings, with differentiation between mice in the Danish Viking area and mice in Norwegian Viking area. Evidently Vikings were important in the foundation of house mouse populations in the northwestern periphery of Europe, and we can see this because particular mitochondrial types became associated (by chance) with particular types of Viking – being transported by them wherever they went. The colonisation of Iceland by mice and people is particularly interesting. The history of human colonisation of Iceland is well-described in the sagas, and two species of mice: house mice and field mice (Apodemus sylvaticus) were taken there, and they occur throughout Iceland. These features create opportunities of using mice as fine-scale proxies of human history.