During the Black Death, the flagellants were groups of people who wandered from town to town whipping themselves and each other with scourges. They believed that the plague was a punishment from God and that their self-mutilation was a form of atonement.
The arrival of the Black Death spread fear and panic throughout Europe. In October 1347, a number of Genoese trading ships docked at Messina, Sicily, with all the crew members dead or dying. This mysterious disease covered the skin in large black boils that seeped puss and blood. Over the next five years, the plague spread all over Europe and killed more than 20 million people, which was almost one-third of its entire population.
Though scientists now realize that fleas on rats carried a bacillus that brought the Black Death and that it also traveled from person to person through the air, then no one had any idea what caused the terrifying disease. People fled from the sick and left them to die in the streets. Some attributed the disease to supernatural causes. Others, however, like the flagellants, claimed it was the result of sins such as heresy, blasphemy, fornication, greed and worldliness. Arriving in a town, the flagellants would ritualistically beat themselves three times a day for 33 1/2 days. When they finished, they would move on to the next town and repeat the ritual. Though the Pope at first tolerated the flagellant movement, eventually he began to believe that the penitents were usurping his authority. In 1349 he denounced the movement, and it disappeared soon afterward.