The Dancing Plague of 1518
A French woman known as Frau Troffea stepped onto a market street in Strasbourg, France, in July of 1518 and began fervently dancing; she didn’t stop for another week. By the end of the month, over 400 other people were uncontrollably dancing; many were dying from heat stroke or exhaustion, and expressed terror at their inability to stop.
This lasted for about a month or two, and was always seen as an extremely strange and bizarre event. Recent investigations to solve this puzzling mystery suggest a mold that might have contaminated their crops; the mold makes people delusional and convulsive. Scholars have also suggested that extreme anxiety over the failure of their crops and a warning about angering St. Vitus led to a mass hysteria; a Christian legend says that anyone who incurred the wrath would be cursed with uncontrollable dancing.