400 People Danced Until They Died

Part 1: A City on the Brink

To understand the Dancing Plague, you need to understand Strasbourg in 1518 — a city already in crisis.

The years leading up to the outbreak had been catastrophic. A sequence of bitter winters and scorching summers had destroyed harvests across the Rhine Valley. Grain prices had skyrocketed. The poor — and Strasbourg had many poor — were starving.

Simultaneously, smallpox and syphilis were tearing through the population. The city's hospitals were overwhelmed. Religious anxiety was intense; Martin Luther had nailed his 95 Theses to the church door in Wittenberg just the year before, and the theological upheaval was reverberating across the Holy Roman Empire.

Into this cauldron of suffering, Frau Troffea began to dance.

Part 2: Patient Zero

The historical record is remarkably detailed about the first case. Multiple sources — including the city council's own minutes, notes from the physician Paracelsus, and chronicles by the local historian Daniel Specklin — describe Frau Troffea's descent into involuntary movement.

On a hot day in mid-July, she stepped into a narrow street and began to dance. Her husband was present and tried to restrain her. She could not be stopped. She danced through the afternoon, through the evening, through the night. By dawn, her feet were bloodied and swollen.

After three days of continuous dancing, her husband petitioned the city council for help. She was carried to the Chapel of Saint Vitus on a hill outside the city, where prayers were offered for her recovery.

She was still dancing when they put her down.

Within days, she was joined by others. By the end of the first week, 34 people were dancing involuntarily in the streets of Strasbourg.

Part 3: The Medical Response

The Strasbourg city council consulted its physicians. In 1518, medicine was a blend of Galenic humoral theory, astrology, and folk practice. The physicians examined the dancers and delivered their diagnosis: the afflicted were suffering from "hot blood" — an excess of the sanguine humor, heated by the summer weather.

Their prescription was counterintuitive but consistent with humoral logic: the dancers needed to dance until the hot blood was purged from their systems. They recommended creating optimal conditions for dancing.

The city council hired professional musicians — pipers and drummers — to accompany the dancers. They cleared two guildhalls and a grain market, spreading hay on the floors. They built a wooden stage. They even hired strong young men to hold up the exhausted dancers and keep them moving.

The number of dancers exploded. Within weeks, approximately 400 people were caught up in the plague.

Part 4: The Death Toll

The dancers were not celebrating. Contemporary accounts are unanimous on this point. The afflicted screamed for help, wept, and begged to stop as their bodies continued to move. Many had to be restrained to prevent them from injuring themselves.

The municipal records document the city council's growing panic. Having initially prescribed dancing, they reversed course. The musicians were dismissed. The guildhalls were closed. The surviving dancers were loaded onto wagons and transported to the mountaintop shrine of Saint Vitus, just outside the city.

Part 5: The Shrine of Saint Vitus

Saint Vitus was the patron saint of dancers, actors, and those suffering from epilepsy and chorea. In the religious framework of 1518, his shrine was the logical place to seek a cure for a dancing affliction.

At the shrine, the dancers were led around a wooden figure of the saint. They were given small crosses and red shoes that had been blessed with holy oil. Prayers were offered. Some accounts describe exorcism-like rituals.

And gradually — over the course of several weeks in August and September — the dancing stopped. The survivors recovered, many with permanent injuries to their feet and legs. Frau Troffea herself survived, though nothing further is recorded about her life.

Part 6: The Theories

Five hundred years of scholarship have produced three major theories for the Dancing Plague.

Theory 1: Ergot Poisoning. Ergot is a fungus (Claviceps purpurea) that infects rye and other cereals. It produces ergotamine, a chemical precursor to LSD. Ergot poisoning (ergotism) has been documented throughout medieval history, causing convulsions, hallucinations, and a burning sensation in the limbs known as "Saint Anthony's Fire."

The problem: ergot typically causes vasoconstriction, which restricts blood flow to the extremities. Sustained, coordinated dancing requires excellent blood flow to the legs. Ergot poisoning generally makes people unable to walk, not unable to stop dancing. The symptoms don't quite match.

Theory 2: Mass Psychogenic Illness. Historian John Waller, who has conducted the most extensive modern research on the plague, argues that it was a case of mass psychogenic illness (MPI) — a stress-induced dissociative state that manifested as involuntary movement.

Waller notes that Strasbourg's population was under extreme psychological stress from famine, disease, and religious upheaval. He also points out that the region had a pre-existing folk belief that Saint Vitus could curse people with dancing plagues. In a population primed by belief and pushed past its psychological limits, the sight of Frau Troffea's dancing may have triggered a cascade of dissociative episodes.

Theory 3: Cult or Sect Activity. Some historians have suggested the dancing may have been connected to heretical religious practices — a devotional trance or ecstatic ritual that spiralled out of control. Evidence for this theory is thin, but not nonexistent; ecstatic dance was a feature of several medieval religious movements.

Part 7: The Other Dancing Plagues

The 1518 event was not unique. Dancing plagues erupted across Europe at least seven times between the 14th and 17th centuries:

• 1374: The largest outbreak. Dozens of towns along the Rhine were affected. Thousands danced in the streets for days or weeks. The affected regions were those hardest hit by the Black Death a generation earlier.
• 1428: A group of women in Schaffhausen, Switzerland, danced involuntarily for days.
• 1518: The Strasbourg event — the best documented and most deadly.

This pattern supports Waller's stress-plus-belief hypothesis but doesn't conclusively prove it. The honest answer, five centuries later, is that we don't fully know what happened in Strasbourg.

Part 8: What It Means

The Dancing Plague forces a confrontation with something uncomfortable: the line between mind and body is far blurrier than we like to think. If hundreds of people can be driven to dance themselves to death by some combination of stress, belief, and social contagion, what does that say about the sovereignty of the individual will?

Modern parallels exist. Mass psychogenic illness still occurs — mysterious illness clusters in schools, "TikTok tics" in teenagers, conversion disorders that spread through social networks. The mechanisms may be better understood now, but the vulnerability hasn't changed.

Frau Troffea started dancing on a hot day in July. Nobody knows why. Nobody knows why she couldn't stop. And nobody knows why, five hundred years later, we still can't fully explain what happened next.