Very little is known about the evolutionary history of the European bison (Bison bonasus). The extensive morphological diversity, particularly in body size, skull and horn shape, has been used by palaeontologists to classify more than 50 species and sub-species during the late Pleistocene (120-11ky BP). Many of these forms appear roughly contemporaneously, and no clear pattern of succession can be discerned. Ancient DNA (aDNA) provides a unique opportunity to directly observe genetic evolution by investigating the changes in genetic structure of species and populations in real time. A previous study of the mitochondrial control region of 448 bone samples from Beringia (Russia/Alaska/Canada) revealed a dynamic series of events through time, including range shifts, migrations, and widespread extinctions (Shapiro et al., 2004). Bison are one of the few species to have survived the mass megafaunal extinction during the Pleistocene/Holocene transition (12-9ky BP). Understanding how will provide insight about how large mammals respond to environmental variation and adapt to periods of rapid climate change. Here we describe the evolutionary patterns observed in high-resolution mitochondrial sequencing data—i.e. complete mitochondrial genomes—from a number of ancient European bison samples, specifically patterns of succession of various bison ecomorphs across a broad geographical and temporal range.