📅 Last updated: 11.10.2026
The Dancing Plague of 1518 was one of the strangest mass events in European history: in the free imperial city of Strasbourg, then part of the Holy Roman Empire, a woman named Frau Troffea stepped into the street in July 1518 and began to dance — and then kept dancing, for days, until dozens and eventually hundreds of her neighbours joined her. Within weeks, the city authorities were grappling with a crowd of people dancing themselves to exhaustion, collapse, and in some accounts death. No single explanation — ergot poisoning, demonic possession, or simple mass hysteria — fits all the evidence. The real story lies in the collision of a specific physical affliction, medieval beliefs about saints and sin, and a city under extreme economic and psychological strain.
- What Actually Happened: The Facts of the Dancing Plague of 1518
- Strasbourg in 1518: A City on the Edge
- Was the Dancing Plague of 1518 Caused by Ergot Poisoning?
- The Medical and Psychological Explanations
- Key Facts and Timeline of the Dancing Plague of 1518
- Why Did the Authorities Respond the Way They Did?
- What the Dancing Plague of 1518 Reveals About Medieval Life
- The Legacy and Lasting Impact of the Dancing Plague of 1518
- Conclusion: A Story About People, Not Just a Curiosity
What Actually Happened: The Facts of the Dancing Plague of 1518
The episode is unusually well documented for a medieval event, and that documentation is what makes it so valuable to historians. Our best contemporary sources are the chronicles, civic records, and letters of Strasbourg’s educated elite, above all the accounts gathered by the humanist writer and city official Sebastian Brant and the physician Paracelsus, who visited the city in 1526 and interviewed survivors and witnesses. Later chroniclers such as the Alsatian historian Johann Schilling (writing in the 1570s) added details, though some of these are embellishments.
The core narrative is consistent. In July 1518, a woman known to history only as Frau Troffea — sometimes rendered as “Troffea” or “Troffea of the guild of St. Vitus” — began to dance in a street in Strasbourg. She danced for roughly four to six days. Within a week, about thirty-four other people had joined her. By August, the number had swollen to as many as four hundred, according to some accounts, though the figure is debated. The dancers reportedly moved through the streets, in market squares, and in guild halls, sweating, shouting, and occasionally begging onlookers to loosen their clothing or fan them.
What followed is the detail that turns a curiosity into a crisis. The city authorities did not try to stop the dancing at first. Instead, following the prevailing medical theory of the day, they encouraged it. Physicians reasoned that the afflicted were suffering from “hot blood” or an excess of choleric humour, and that the cure was to let the dancing run its course in a controlled space. The city therefore cleared two guildhalls — the Guildhall of the Mirror and the Guildhall of the Hoof — and set up a stage in the grain market. Musicians were hired to play, because the dancers seemed unable to stop without music. Strong men were paid to hold the dancers upright so they could keep moving.
The policy backfired catastrophically. The dancing spread further, and the physical toll mounted. Chroniclers report dancers collapsing from exhaustion, heart attacks, and strokes; some accounts claim fifteen deaths per day at the peak, though that number is almost certainly exaggerated. By late summer, the authorities reversed course. They banned music in the affected areas, forbade public assembly, and — most revealingly — outlawed dancing altogether in the city, threatening fines and imprisonment. The episode subsided by early autumn, though sporadic cases were reported into 1519.
Strasbourg in 1518: A City on the Edge
To understand why the Dancing Plague of 1518 erupted where and when it did, you have to understand Strasbourg in the 1510s. It was not a random backdrop. The city was a wealthy but anxious place, and the anxieties were specific and cumulative.
Famine, disease, and the grain crisis
The years before 1518 were brutal across the Rhineland. A series of poor harvests in 1516 and 1517 drove up grain prices sharply. Strasbourg, like most medieval cities, depended on imported grain from the surrounding countryside, and when the harvest failed, the poor starved. Contemporary sources describe bread riots, vagrancy, and a rising death toll among the labouring classes. The city’s hospitals and almshouses were overwhelmed. This was not a background hum of hardship; it was an acute, visible crisis that dominated daily life.
On top of hunger came disease. Syphilis — then called the “French disease” or morbus gallicus — had swept through Europe since the 1490s, and Strasbourg, as a major trading city on the Rhine, was hit hard. Outbreaks of plague and “the sweating sickness” recurred. The population was physically depleted and psychologically primed for catastrophe.
Religious anxiety and the cult of St. Vitus
Strasbourg was also a city in the grip of intense religious anxiety. The Protestant Reformation was just beginning — Martin Luther posted his Ninety-five Theses in 1517, the year before the outbreak — and Strasbourg would become one of the earliest and most important Protestant cities, but in 1518 the confessional lines were not yet drawn. What existed was a pervasive fear of divine punishment, demonic activity, and the wrath of the saints.
Central to the Dancing Plague is the cult of St. Vitus. Vitus was a Sicilian martyr, supposedly killed under the emperor Diocletian around 303 CE. By the Middle Ages, he had become the patron saint of dancers, actors, and — crucially — of those afflicted by a condition called chorea, from the Greek for “dance.” The condition was known as St. Vitus’s Dance (later identified with Sydenham’s chorea, a neurological disorder linked to rheumatic fever). Sufferers experienced involuntary jerking and twitching movements, and the affliction was widely believed to be a punishment sent by the saint for sin or impiety.
Strasbourg had a particular connection to Vitus. The city’s cathedral housed relics associated with him, and there was a chapel dedicated to him nearby. Pilgrims travelled to Strasbourg to be cured of St. Vitus’s Dance. The belief that the saint could inflict compulsive dancing as a punishment was therefore not abstract theology in Strasbourg — it was local, familiar, and deeply felt.
Was the Dancing Plague of 1518 Caused by Ergot Poisoning?
The most popular modern explanation — repeated in countless documentaries and articles — is ergotism. Ergot is a fungus (Claviceps purpurea) that grows on rye and other cereals, especially in damp conditions. Consuming ergot-contaminated bread can cause convulsions, hallucinations, and a burning sensation in the limbs, a condition historically called “St. Anthony’s Fire.”
It is a seductive theory, and it has real merit as a partial explanation. The harvest failures of 1516–17 would have created exactly the damp, poor-quality grain in which ergot thrives. Some ergot alkaloids are chemically related to lysergic acid diethylamide (LSD), which can produce hallucinatory and compulsive behaviour. But the theory has serious problems when applied to this specific event:
- Ergotism causes convulsions, not sustained dancing. The muscle spasms of ergot poisoning are violent and involuntary, and they do not resemble the coordinated, rhythmic dancing described by witnesses.
- Ergotism is not contagious. The Strasbourg dancers spread the behaviour from person to person over weeks, which poisoning cannot explain.
- Ergotism would have affected entire households that shared the same bread, including children and the elderly, not primarily adults who chose to join a public spectacle.
- No other symptoms of ergotism — gangrene, burning limbs, or widespread convulsions — are reported in the Strasbourg sources.
The most defensible position is that ergot may have played a contributing role in a few cases, but it cannot be the primary cause. The pattern of the outbreak — its spread, its selectivity, and its psychological character — points elsewhere.
The Medical and Psychological Explanations
Modern historians and physicians have offered several overlapping explanations, and the best answer is probably a combination of them.
Mass psychogenic illness
The leading explanation today is mass psychogenic illness (sometimes called mass hysteria): a phenomenon in which real physical symptoms spread through a group by psychological contagion rather than a shared pathogen. The Strasbourg dancers were not faking. They experienced genuine, involuntary compulsion — but the compulsion was generated by belief, stress, and social suggestion rather than by a toxin.
This fits the evidence remarkably well. The outbreak began with a single individual and spread through visual contact and social imitation, exactly as psychogenic outbreaks do. It affected people who were already under extreme stress. It was shaped by a pre-existing cultural script — the belief that St. Vitus could punish sinners with compulsive dancing — which gave sufferers a ready-made way to express their distress. And it resolved when the social conditions changed: when the authorities stopped reinforcing it, banned music, and treated it as a crime rather than an illness.
The “dancing mania” tradition
The 1518 event was not isolated. It was the most famous in a long series of dancing manias recorded across the Rhineland and Low Countries from the eleventh to the sixteenth centuries. The most famous earlier outbreak occurred in 1374, when crowds in Aachen, Cologne, and along the Rhine danced in the streets for days, often in a state of trance, and were sometimes led to shrines of St. Vitus for healing. In 1237, a similar episode was reported in Erfurt, where children danced and jumped from the city walls, according to the chronicler. These earlier events established a cultural template: dancing mania was a known, feared, and religiously interpreted phenomenon. When Frau Troffea began to dance in 1518, she was stepping into a role that her culture already recognised.
Key Facts and Timeline of the Dancing Plague of 1518
| Date | Event | Key Figures / Places |
|---|---|---|
| 1516–1517 | Poor harvests, famine, and grain price spikes across the Rhineland | Strasbourg, Alsace |
| July 1518 | Frau Troffea begins dancing in a Strasbourg street; ~34 join within a week | Frau Troffea; Strasbourg |
| August 1518 | Outbreak peaks; authorities encourage dancing in guildhalls and the grain market | Guildhall of the Mirror; Guildhall of the Hoof |
| Late summer 1518 | Dancers collapse and some die; city reverses policy, bans music and dancing | Strasbourg city council |
| 1519 | Sporadic cases continue before the episode ends | Strasbourg and surrounding region |
Why Did the Authorities Respond the Way They Did?
The city council’s response is one of the most instructive parts of the story, because it reveals how medieval people reasoned about affliction. The initial decision to encourage the dancing was not stupidity; it followed from the dominant medical theory of the time.
Medieval medicine was built on the humoral theory inherited from Galen and Hippocrates. Health depended on the balance of four humours: blood, phlegm, yellow bile (choler), and black bile (melancholy). An excess of a humour could be expelled through sweating, purging, or exertion. Dancing, especially vigorous dancing that produced heat and sweat, was therefore a logical therapy for a “hot” or “choleric” condition. Physicians advised the city to let the afflicted dance it out.
The reversal came when the therapy clearly failed. As deaths mounted and the crowd grew, the council shifted from a medical to a moral and legal frame. Dancing was banned, music silenced, and the afflicted threatened with punishment. This shift — from treating the dancers as patients to treating them as criminals or sinners — is a recurring pattern in the history of mass illness. It also worked, or at least coincided with the outbreak’s decline, because it removed the social reinforcement that kept the behaviour going.
It is worth noting what the council did not do. They did not execute the dancers, as some sensationalised accounts suggest. They did not burn them as witches. The response was pragmatic and, by the standards of the day, relatively restrained.
What the Dancing Plague of 1518 Reveals About Medieval Life
The episode is often told as a bizarre curiosity, a medieval oddity to be gawked at. That framing misses its real value. The Dancing Plague of 1518 is a window into the mental and physical world of late medieval Europe, and what it shows is both alien and recognisable.
- It shows the reality of famine and disease. The dancers were not carefree revellers. They were people living through hunger, epidemic, and economic precarity, and their bodies responded to that stress in a dramatic, public way.
- It shows the power of religious belief. The idea that St. Vitus could punish sin with compulsive dancing was not a metaphor to the people of Strasbourg. It was a concrete, terrifying possibility, and it shaped how they experienced and interpreted their own symptoms.
- It shows how tightly connected medieval communities were. In a city of perhaps 20,000 to 25,000 people, everyone knew everyone. Behaviour spread through crowds, churches, markets, and guildhalls. There was no privacy in which private distress could remain private.
- It shows the limits of pre-modern medicine. Humoral theory was sophisticated, internally coherent, and wrong in ways that made the crisis worse. The city’s best medical advice amplified the outbreak.
“They danced in the streets, in the squares, and in the churches, and no one could stop them, until at last the magistrates forbade all music and dancing, and the affliction ceased.”
— Paraphrase of the account attributed to the Strasbourg chronicles, as summarised by later historians
The Legacy and Lasting Impact of the Dancing Plague of 1518
The Dancing Plague of 1518 occupies a strange place in history. It changed nothing politically, ended no dynasty, and won no battles. Yet it has proved remarkably durable in cultural memory, and it has become a touchstone for several modern fields.
For medical history, it is a classic case study in mass psychogenic illness and in the history of chorea and movement disorders. Neurologists still cite it when discussing functional neurological disorders, and it appears in textbooks on conversion disorder. For psychology and sociology, it is a foundational example of social contagion, cited alongside the Tanganyika laughter epidemic of 1962 and the “Strasbourg dancing” of 1518 as evidence that behaviour can spread through populations in ways that mimic disease.
For cultural history, the event has been endlessly reinterpreted. It appears in novels, plays, and films — most notably in the 2011 novel The Dancing Plague by Clare Clark and in numerous popular history books. It has been invoked as a metaphor for everything from religious ecstasy to collective burnout. Each generation finds its own meaning in the image of a city dancing itself into collapse.
The most important legacy, however, may be historiographical. The Dancing Plague of 1518 survives in the record because a handful of educated men — Brant, Paracelsus, Schilling — thought it worth writing down. Their accounts are partial, contradictory, and shaped by their own assumptions. Modern historians have to read them critically, separating what witnesses plausibly saw from what they inferred. That process of critical reading is itself a lesson in how history is made.
Conclusion: A Story About People, Not Just a Curiosity
The real story of the Dancing Plague of 1518 is not that medieval people were credulous or strange. It is that they were human beings living under conditions of extreme stress, in a world where famine, disease, and religious fear were constant companions, and where the line between the physical and the psychological was understood very differently than it is today. Frau Troffea and the hundreds who followed her were not performing a spectacle. They were experiencing something real, and their bodies and minds responded to that reality in the only language their culture had available.
The episode endures because it sits at the intersection of so many things we still care about: the relationship between mind and body, the power of belief, the vulnerability of communities under strain, and the difficulty of explaining human behaviour that seems to defy reason. The dancers of Strasbourg did not leave us a clear answer. What they left us is a question that is still worth asking — about what happens when a society’s pressures become so great that they break out into the streets, and about how we respond when they do.