In early July of 1518, a woman called Frau Troffea stepped out of her house in the city of Strasbourg, in the upper Rhine, and began to dance in the narrow street outside her door. She continued for several days. Her husband tried to make her stop. She did not. The city physicians were called. They observed her, and then, having no better suggestion, recommended that she keep going. After about a week she fell down and was carried, unconscious, to the shrine of Saint Vitus in the hills above the town. By that point, thirty-four other people in Strasbourg had begun to dance too.
By August the number was, according to the surviving city chronicles, around four hundred. The Strasbourg city council, faced with hundreds of citizens dancing in the streets and dying — at first from exhaustion, then from heart attacks and strokes — issued an emergency ordinance. The council ordered the construction of two wooden stages in the city’s grain market and outside one of the gates, hired pipers and drummers to provide music, and instructed the dancers to keep going until they were cured.
The treatment did not work. Estimates of the death toll vary; the city chronicler Daniel Specklin, writing a few decades later, says “about fifteen a day died for many days.” Modern historians, working from the limited records, estimate fifty to a hundred deaths over the course of the episode. The dancing began to subside in early September. By the end of the month it had stopped.
What had caused it is still, five hundred and eight years later, an unsettled question.
What the documents actually say
The Strasbourg dancing plague of 1518 is unusually well-documented for a sixteenth-century epidemic. There are at least seven contemporary or near-contemporary sources: physicians’ notes, city council minutes, parish records, two chronicles (including Specklin’s), and a brief account by the Swiss physician Paracelsus, who visited the city around 1526 and wrote about the event in his treatise On the Dancing Disease.
The accounts agree on the timeline (mid-July to early September 1518), the starting point (Frau Troffea, although Specklin spells it Troffea while others spell it Trauffea), the city’s response (stages and musicians), and the fact that people died. They disagree about how many people died and about the cause.
Specklin attributed the dancing to a heated bath taken at the wrong moment. The Strasbourg physicians, in their initial report to the council, suggested that it was caused by “hot blood” in the brain — a malfunction of the humoral balance — and prescribed continued dancing to “work it out.” The Catholic theologians attributed it to the wrath of Saint Vitus, the third-century martyr who, in late-medieval German tradition, had been associated with involuntary movement disorders. The Protestant historians of the seventeenth century, looking back, suggested mass hysteria triggered by religious fear.
This was not the first time it had happened. Outbreaks of involuntary group dancing — known in the medical literature as choreomania — were recorded across the Rhine valley and the Low Countries from at least 1374, when a major outbreak in Aachen affected several thousand people. There were further outbreaks in Maastricht in 1428, in Cologne in 1463, and in Zurich in 1519. The Strasbourg event was the last and the best-documented. There have been no recorded outbreaks of large-scale dancing mania since the seventeenth century.
The leading modern theory
The most thorough modern investigation of the 1518 episode has been done by the British medical historian John Waller, whose 2008 book A Time to Dance, a Time to Die is the standard account, and whose 2009 Lancet article laid out the medical framework most historians now accept.
Waller rejected the most popular alternative explanation — ergot poisoning. Claviceps purpurea, the fungus that grows on damp rye and contains psychoactive alkaloids related to LSD, had been suggested by twentieth-century writers as the cause of medieval dancing manias, including the 1518 outbreak. The problem, as Waller pointed out, is that ergot poisoning typically causes either convulsions or gangrene, not sustained rhythmic dancing. The dancers in Strasbourg were not having seizures. They were dancing. People with ergotism cannot dance — their blood vessels are constricting and their limbs are dying.
What Waller proposed instead is a more diffuse explanation: a mass psychogenic illness, triggered by acute social and religious stress in a community already steeped in the legend of Saint Vitus.
The summer of 1518 had been a terrible one in Strasbourg. The previous year’s harvest had failed. Famine was setting in. The Rhine had flooded in the spring. A new outbreak of syphilis, only twenty-five years after the disease had first appeared in Europe, was sweeping the city. Refugees from rural districts were arriving and dying in the streets. Plague had been reported in the surrounding countryside. The Catholic Church, on the eve of the Reformation, was preaching divine punishment.
In this environment, Waller argued, the local belief that Saint Vitus could induce involuntary dancing as a curse — a belief that had been current in the Rhine valley for at least 150 years — created a kind of cultural script. A first sufferer (Frau Troffea), pushed beyond endurance by personal stress or grief, entered a trance state and began to dance. Her behavior was immediately interpretable in religious terms by everyone who saw her. The pattern was contagious because the framework existed for understanding it.
The dancers, in this reading, were not pretending. They were in genuine altered states — dissociation, trance, fugue. The city council’s response of building stages and hiring musicians, deeply strange to a modern reader, was a rational response within their own framework: the curse was real, the only known cure was to dance it out, the city’s job was to provide the venue.
The dancing stopped, Waller suggests, when the most affected people were taken on pilgrimage to the Saint Vitus shrine at Saverne, about forty kilometers away. The pilgrimage itself functioned as a culturally appropriate termination of the curse. Recovery rates after the pilgrimage seem to have been high.
It is an explanation that does not fully satisfy anyone. The ergot theorists are still around. Some modern psychiatrists prefer to call it a culturally bound dissociative disorder. Others have proposed a now-extinct neurological infection. None of these explanations can be tested.
The best record we have is Specklin’s. His chronicle survives in a sixteenth-century manuscript in the National and University Library of Strasbourg. In one of the marginal notes, the chronicler wrote: Sie tanzten bis sie tot fielen — they danced until they fell dead.