Dancing mania (also known as dancing plague, choreomania, St John’s Dance and, historically, St. Vitus’ Dance) was a social phenomenon that occurred primarily in mainland Europe between the 14th and 17th centuries. It involved groups of people dancing erratically, sometimes thousands at a time. The mania affected men, women, and children, who danced until they collapsed from exhaustion. One of the first major outbreaks was in Aachen, Germany, in 1374, and it quickly spread throughout Europe; one particularly notable outbreak occurred in Strasbourg in 1518.

The Pied Piper of Hamelin (German: Rattenfänger von Hameln) is the subject of a legend concerning the departure or death of a great many children from the town of Hamelin (Hameln), Lower Saxony, Germany, in the Middle Ages. The earliest references describe a piper, dressed in multicolored clothing, leading the children away from the town never to return. In the 16th century the story was expanded into a full narrative, in which the piper is a rat-catcher hired by the town to lure rats away with his magic pipe. When the citizenry refuses to pay for this service, he retaliates by turning his magic on their children, leading them away as he had the rats. This version of the story spread as a fairy tale. This version has also appeared in the writings of, among others, Johann Wolfgang von Goethe, the Brothers Grimm and Robert Browning.