European Microtus voles have undergone a series of colonization events from the initial appearance probably from the East over various speciation processes to very recent range expansions and contractions due to changes in agricultural land use. Some of these processes are, however, likely to differ from many other taxa studied so far due to the relative cold tolerance and preference for open habitats. We examine the timing and mode of these colonization processes with molecular and statistical methods in a comparative approach. This includes also the analysis of patterns of gene flow at suture zones, and the probably human-induced colonization of the Orkney Islands by Microtus arvalis in the Neolithic.