Final answer:
The Black Death, or the bubonic plague, was a deadly epidemic that occurred in Europe during the mid-fourteenth century, resulting in the death of millions of people. It was caused by the bacterium Yersinia pestis, spread through fleas carried by rats. The disease had far-reaching social, economic, and cultural effects on Europe.
Step-by-step explanation:
The Black Death, also known as the bubonic plague, was a devastating epidemic that occurred in Europe during the mid-fourteenth century. It was caused by the bacterium Yersinia pestis and resulted in the death of millions of people, roughly one-third of Europe's population. The disease spread through fleas that infested rats, which were unknowingly brought back by Genoese merchants from the Black Sea.