The Black Death was one of the most devastating outbreak of a pandemic disease in human history, resulting in the deaths of an estimated 75 to 200 million people peaking in Europe in the years 1346 - 1353
Although there were several competing theories as to the etiology of the Black Death, analyses of DNA from victims in northern and southern Europe published in 2010 and 2011 indicates that the pathogen responsible was the Yersinia pestis bacterium, probably causing several forms of plague.
This was a widespread epidemic of the Bubonic Plague that passed from Asia and through Europe in the mid fourteenth century. The first signs of the Black Plague in Europe were present around the fall of 1347. In the span of three years, the Black Death killed one third of all the people in Europe.