An important fraction of the medieval population in Europe died during the mid-14th century in a period of less than ten years (1346-1353 AD) due to the second largest spread of Yersinia pestis in human history, an episode also known as the Black Death . Estimates based on archaeology and historical documents range between 25% to 50% of the population being decimated, with important differences among different cities and regions . An important question that remains to be properly addressed is the extent to which genetic evidence agrees and supports one or another of these estimates. Do we observe a magnitude of events corresponding to ~25% or ~50% human loss? Are we able to capture differences by region and do these also correspond to previous evidence from other disciplines?
I am using a panel of Eurasian individuals geographically spanning from Spain to the Urals and further east to China. I will apply then methodologies that recover fluctuations in population size during the recent past, such as IBDne .
 Zietz, B. P., & Dunkelberg, H. (2004). The history of the plague and the research on the causative agent Yersinia pestis. International Journal of Hygiene and Environmental Health, 207(2), 165–178. http://doi.org/10.1078/1438-4639-00259
 Browning, S. R., & Browning, B. L. (2015). Accurate Non-parametric Estimation of Recent Effective Population Size from Segments of Identity by Descent. American Journal of Human Genetics, 97(3), 404–418. http://doi.org/10.1016/j.ajhg.2015.07.012