Plague is the most terrifying infective disease that raged in Europe till 1750. Only one century ago, the bacterium Yersinia pestis was identified as the causative agent of the last pandemic. But up today it remains high controversial and not fully proven that this species was in fact responsible for all the known plague epidemics in the past.

And even in the case it did indeed caused all the plague waves, it still remains uncertain which variants or subspecies of the bacterium caused them. Although the three great pandemics are referred to ‘plague’ some historians speculate that other infective agents may have been responsible for the contagion. Every medieval or later archaeological site with one or more mass graves and without associated historical records is trendily attributed to plague, although several other infective or not infective causes (like famine or catastrophic events) might have led to the same collective death. In order to diag-nose the true origin of the epidemics, a molecular approach (aDNA) is one of the most appropriate means. The analysis of ancient DNA from the skeletons of plague victims and the application of new genome-wide sequencing methods will not only reveal the ultimate cause of death but eventually even the phylogenesis of the causative agent.
International cooperation partners provide additional support for the interpretation of the results.

The project is supported by the University of Mainz (FP1_2007: Evolutionsgeschichte des Pesterregers Yersinia pestis and by DFG (BR2965/2-2: Infektionsresistenz gegen Cholera und Pest als Selektionsfaktor menschlicher Evolution)