dle Ages, the chronicles of this being a supernatural happening are (probably) false, but the pattern of groups of people performing a dance that they could not escape from is anything but fictional.
In another incident of fatal choreography, 200 dancers were involved in an episode on a bridge over the Moselle River. According to accounts, the dancing force was so great that it led to the bridge's collapse, and all of the dancers were killed. Similar stories also spread throughout the Middle Ages as a sort of bogeyman (or boogieman in these cases). Dancing or acting in ways that were considered impious in general was perceived as dangerous in medieval society, so the act of doing so had to result in almost biblical consequences, like dancing until a bridge collapsed. However, even if the tales were used as moral panic fodder, the idea of mass groups of people dancing for weeks or even months on end was reality.
Pathology Of The Dance
As David Byrne once said while doing his own dance in the "Once in a Lifetime" music video, "Well ... how did I get here?" There is no definite answer to this, but there are sound theories.
At the time, of course, this was chalked up to demonic possession. Who could blame anyone for guessing this? Those afflicted were said to be in a trance-like state, and many of them cried out for help and were visibly in pain, indicating that the dance was not their choice. While the dancers may not have been the victims of dark magic, keep this pinned to the idea board, as it will be important later on.
One modern theory is that the doomed dancers were suffering from ergotism. Ergot is a type of fungus that grows on rye. Effects of ergot ingestion include hallucinations and tremors, and instances of ergotism in medieval Europe are well documented. While this theory does offer an explanation for why something resembling dancing occurred, it does not explain why the episodes lasted as long as they did. The 1518 dancing plague in Strasbourg may have lasted two months, while ergotism's effects typically do not.
A more complex take on the cause of the hysteria comes from John Waller, a medical historian. Waller notes the severe psychological stresses were at play in areas where dancing plagues occurred. Life in the Middle Ages was brutal and short, and this was especially true in the regions and times where dancing outbursts happened. Take Strasbourg in 1518, for example. These were people dealing with poor harvests, which meant even harsher living. Diseases like syphilis were also raging throughout the area. The stress of this eventually broke people like poor Frau Troffea down.
As for why they went with dancing as an emotional reaction, Waller also discusses the idea of the people acting out the beliefs that they held. In our modern world, we have been going through tremendous stress too, but you don't see anyone dancing their worries away (outside of those first few months of the pandemic where everyone did TikTok dances, but that was just out of boredom). In the Middle Ages, though, the people who lived in the areas affected by dancing mania had firmly held beliefs about spirits and demons. Possession felt as real to them as the cycle of the harvest. When times became too difficult, some people may have been psychologically beaten until they believed that they were victims of possession. Then, others joined as mass hysteria spread.
TL;DR: pre-existing beliefs + extreme stress = a dancing fever you can't sweat out
What's The Cure For Dancing Fever Then?
Well, it's not music, that's for sure.
During the 1518 dancing outbreak, authorities logically concluded that the way to end the nonstop party was to encourage the entranced dancers to keep going until they ran out of energy. They brought in musicians to give the dancers a soundtrack and essentially turned the afflicted Strasbourg into a music festival. Instead of ending the dancing plague, this just encouraged it to keep going. It was a good effort, though.
Instead, the dancing ceased in 1518 when the afflicted dancers were taken to a shrine for Saint Vitu