St. John's Dance: Medieval Aachen's Mass Hysteria
A mysterious outbreak of compulsive dancing erupted in Aachen on June 24, 1374, with hundreds of people reportedly unable to stop dancing until they collapsed from exhaustion, injury, or heart attacks. The phenomenon, known as St. John's Dance or dancing mania, spread to Cologne, Liege, and other cities in the Rhineland. Sufferers screamed, hallucinated, and begged for help while unable to control their movements. Similar outbreaks occurred periodically in Europe between the 14th and 17th centuries, including the famous Strasbourg dancing plague of 1518. Explanations range from mass psychogenic illness (stress-induced mass hysteria) to ergotism (poisoning from ergot fungus in grain, which produces LSD-like compounds) to religious fervor. No single theory fully accounts for all documented cases.
June 24, 1374
652 years ago
Key Figures & Places
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