Between 1328 and 1351, the bubonic plague, commonly known as the Black Death, killed approximately one third of the population of Europe. The widespread nature of the disease, along with its horrific symptoms, inspired Europeans to go to any lengths to avoid it.
A number of superstitious and pseudo-scientific beliefs arose surrounding the causes of the spread of the bubonic plague. In their efforts to avoid the disease, people went to outrageous extremes, including living in sewers, barricading themselves from society, and flagellating one another with whips.
One widely used trick to avoid the plague was an early form of aromatherapy. Doctors instructed patients to carry flowers on their person, thinking that the sweet odor would keep the plague at bay. Herbal packets were also used as an alternative. Those in the upper classes began using balls of perfume called pomander, a custom which continued after the plague was wiped out.
Catholics believed that the plague was God's punishment for evil in society, spurring some to take extreme actions, such as self flagellation, in an attempt to gain forgiveness. Others believed that the disease was the will of God, and that they were powerless to resist or try to prevent its spread.
Some people moved into sewers, having heard that the plague was airborne. They believed that the unclean air would prevent the fresh, plague-ridden, air from entering the sewers. Those who subscribed to this idea often became infected, either with the bubonic plague or with a disease from the unclean conditions of the sewers.
A more outrageous remedy involved shaving a live chicken and strapping the chicken to an infected person's swollen lymph nodes. The chicken would get sick, and then get washed for the process to happen again until one of the two became healthy.