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