51 Historical Facts That Are Totally Messed Up | 8. After Pope Gregory IX associated cats with devil worship, cats throughout Europe were exterminated in droves. 9. This sudden lack of cats lead to the spread of disease because infected rats ran free. The most devastating of these diseases, The Bubonic Plague, killed 100 million people.
Bubonic plague infection causes tiny blood vessels in the hands and fingers to clog up and cut off circulation. Without blood, the flesh dies and turns black (called "gangrene"). This is why in the Middle Ages bubonic plague was called "the Black Death." In the 14th century it killed an estimated 25 million people, or 30–60% of the European population.
Ring Around The Rosie. This rhyme dates back to the Great Plague of London in 1665. The symptoms of bubonic plague included a rosy red ring-shaped rash, which inspired the first line. It was believed that the disease was carried by bad smells, so people frequently carried pockets full of fresh herbs, or "posies." The "ashes, ashes" line is believed to refer to the cremation of the bodies of those who died from the plague.