The Black Death was a devastating pandemic that originated in China in the 1330s and killed an estimated 30-60% of Europe's population by the late 1340s. Caused by the bacterium Yersinia pestis, it spread rapidly through trade routes and infected populations with little immunity. There were three main forms: bubonic, pneumonic, and septicemic plague. Factors like poor sanitation, war, and famine exacerbated its spread. It disappeared in the late 19th century due to improved hygiene, the spread of the more resistant brown rat replacing the black rat, and the bacterium slowly dying out in human hosts.

1. The Black Death A Pandemic that Changed The Middle Ages

7. The Plague Doctors