In the sixth century, an outbreak of bubonic plague killed forty percent of Constantinople's population.
Bubonic plague is one of three types of plague caused by bacterium Yersinia pestis.
The bubonic plague is believed to have caused the Black Death that swept through Asia, Europe, and Africa in the 14th century and claimed the lives of an estimated 50 million people. This was nearly 25% to 60% of the European population. Since the plague killed so many of the working population, wages rose due to the demand for labor.
