The dancing plague of 1518: the collective enigma that made hundreds dance to collapse

In July 1518, in the streets of Strasbourg (then part of the Holy Roman Empire), a woman named Frau Troffea began dancing alone and without music in a public square. It was no celebration: her expression was one of complete trance and agony. Far from stopping after a few hours, she continued moving for six consecutive days until her feet bled profusely.

Within weeks, the phenomenon spread uncontrollably:

• By early August, more than thirty neighbors had joined the frantic dance.
• By September, the affected crowd numbered around four hundred people, many of whom danced until falling unconscious or dying of cardiac exhaustion and starvation.

Desperate, the authorities consulted local physicians, who ruled that it was not demonic possession, but a physical affliction caused by overheated blood. To purge the excess energy, the city council made an unusual decision: they cleared a grain market, built wooden stages, and even hired professional musicians and dancers to accompany those affected day and night, mistakenly believing that the only cure was to dance to complete exhaustion.

The measure worsened the outbreak by drawing in more vulnerable onlookers. Modern historians, such as specialist John Waller, rule out ergot poisoning (ergotism) due to the sustained motor endurance required, concluding instead that it was the best-documented case of mass psychogenic illness, triggered by severe famines, previous epidemics, and deep religious suggestion tied to the wrath of Saint Vitus.