3. The Black Death in Asia, North Africa, and Europe
The bacterium which caused the Plague of Justinian was yersinia pestis. The Justinian plague was a different strain than that which is commonly known as the Black Plague, though the same virus. The Black Plague was bubonic plague, entered Europe from Asia, and then spread to North Africa. It originated in China, spread to the west via the Silk Road and in the hulls of merchant ships, carried by infested rats. By the middle of the 14th century, it was in the Russian steppes and Ukraine. It was so deadly two full centuries were required to recover the loss of population it caused. At least 75 million people succumbed; some estimate the deaths to have numbered over 200 million, which included up to 60% of the people of Europe.
One hundred thousand people died in Paris. Germanic and English settlements suffered death rates of 60% and up. The death rate obviously depleted the workforce. Crops rotted in the fields in the absence of workers to harvest them, costs of food increased, and starvation ensued. Monasteries and convents often served as hospitals. The priests, monks, and nuns who served the sick were struck down, and clerical establishments were abandoned. There are climatologists who speculate the Black Death contributed to the Little Ice Age, when fields formerly in crops returned to their wooded state. The added forests contributed to cooling. The plague led to Christian attacks on Jewish communities throughout Europe, believed by some to be divine retribution for sins.