Summary: <br> On June 24, 1374 – 645 years ago today – the men, women, and children of the Rhineland city of Aachen began to dash out of their houses and into the streets, where – inexplicably, compulsively and uncontrollably – they began to twist and twirl, jump and shake, writhe and twitch until they dropped from exhaustion or simply dropped dead. Real disco inferno, boogie-fever stuff. It was the first major occurrence of what would come to be known as “dancing plague” or “choreomania”, which over the next years was to spread across Europe.<br> <br> <br> <br> The authorities typically had music played during outbreaks of dancing plague, as it was believed to somehow “cure” the mania. A painting by Pieter Brueghel the Younger, after drawings by his father. Pieter Breughel the Younger, painting.<br> <br> <br> <br> There had been small outbreaks before, going back to the seventh century. An outbreak in 1237 saw a group of children jump and dance all the way from Erfurt to Arnstadt in what today is central Germany, a distance of some 13 miles. It was an event that might very well have given rise to the legend of the Pied Piper of Hamelin.<br> <br> <br> <br> But the outbreak in Aachen 645 years ago today was big: before it was over thousands upon thousands of men, women and children had taken to the streets as the “dancing plague” spread from Aachen to the cities of Cologne, Metz, Strasbourg, Hainaut, Utrecht, Tongeren, and then across Belgium, France, Germany, and the Netherlands.<br> <br> <br> <br> This huge outbreak came to be called “St. John’s Dance”, though at other times and in other places it was called “St. Vitus’ Dance”. (These names were coined based on the assumption that the “plague” was the result of a curse cast by either St. John the Baptist or St. Vitus, the former having been beheaded by Herod Antipas between 28 and 36 CE and the latter martyred in 303 during the persecution of Christians by the co-ruling Roman Emperors Diocletian and Maximian.) <br> <br> <br> <br> Writing in his book The Black Death and the Dancing Mania, the German physician and medical writer Justus Friedrich Karl Hecker (1795-1850) describes St. John’s Dance this way:<br> <br> <br> <br> “They formed circles hand in hand and appearing to have lost all control over their senses, continued dancing, regardless of the bystanders, for hours together, in wild delirium, until at length they fell to the ground in a state of exhaustion. They then complained of extreme oppression, and groaned as if in the agonies of death, until they were swathed in cloths bound tightly round their waists, upon which they again recovered, and remained free from complaint until the next attack.”<br> <br> <br> <br> The American medical sociologist Robert Bartholomew (born 1958) is an expert on mass hysteria, mass psychological illness, and hysterical contagion. Writing in his book Little Green Men, Meowing Nuns and Head-Hunting Panics: A Study of Mass Psychogenic Illness and Social Delusion (Macfarland, 2001), Bartholomew observes that sometimes tens of thousands of people would dance for hours, days, weeks, and even months at a time and that throughout, dancers screamed, laughed or cried. And while we do not know whether the dancing was spontaneous or organized, the dancers themselves appeared to be unconscious and unable to control themselves. Bartholomew further notes that some dancers “paraded around naked, made obscene gestures and acted like animals”, while still others managed to have sexual intercourse while they danced. (This is all starting to sound like Studio 54 in New York City during the 1970s.)<br> <br> <br> <br> Choreomania with Disco Granny at Studio 54, 1978<br> <br> <br> <br> So to the question each and every one of us is asking: what could cause such mass frenzy? Regrettably (but not unexpectedly), the answer is that no one really knows for sure. Of course,
