The Dancing Plague of Strasbourg (1518): The Summer Hundreds Could Not Stop Dancing.

What happened in Strasbourg, in a paragraph.

Some time in the second week of July 1518 — the date most often given in the modern literature is July 14, although the contemporary chronicles do not all agree on the calendar day — a woman identified in the Strasbourg city records and the chronicle of the imperial architect Daniel Specklin only as Frau Troffea (the surname is sometimes rendered as Trofea, Troffea, or Troïffa in different sources) began to dance, alone, in a public street in the city. She did not stop. Within a few days, by the most conservative estimate, more than thirty other people had joined her; within a month, contemporary observers spoke of somewhere between several dozen and several hundred people dancing through the streets, courtyards, marketplaces, and church squares of Strasbourg, many of them apparently unable to control their movements, some collapsing from exhaustion, several reportedly dying of stroke, heart attack, or sheer physical collapse. The municipal council of Strasbourg, after consulting the city's physicians (who attributed the affliction to an imbalance of the bodily humours and specifically to "hot blood"), responded by clearing two guild halls, the open-air grain market, and a wooden stage erected near the horse fair for the use of the dancers, and by hiring musicians and professional dancers to accompany them — on the medical theory that the affliction could be discharged only by being danced out. The intervention appears to have made matters worse rather than better; reports of new cases continued into August. Some time in early September, on the advice of either a different group of physicians or the church (the chronicles diverge), the policy was reversed: music was forbidden, dancers were marched out of the city walls to the shrine of St. Vitus in the hills of Saverne (the modern Mont Sainte-Odile region of Alsace), and the affliction subsided. By late September the outbreak was over. The Strasbourg city chronicles, the contemporary medical writings of the physician Paracelsus (who passed through Strasbourg in 1526 and discussed the incident in his subsequent writing on chorea), and the records of the city's town councillors collectively constitute one of the best-documented mass psychogenic episodes of the late medieval and early modern period in Europe. The modern medical literature has proposed at least three substantive explanations — ergot poisoning, mass psychogenic illness against a background of acute communal stress, and the cult of St. Vitus — none of which is universally accepted.

The documented record.

The contemporary sources

The Strasbourg dancing plague is well-documented for an event of its period. Verified The primary contemporary sources include: the chronicle of Daniel Specklin (1536–1589), Strasbourg's later imperial architect, who incorporated earlier sixteenth-century chronicle material into his manuscript chronicle; the city's own minutes of the council (the Strassburger Stadtrat) for the months of July, August, and September 1518; the parish records of the church of St. Vitus, which received pilgrim dancers in September; the writings of the physician Theophrastus Bombastus von Hohenheim ("Paracelsus") whose 1526 visit produced his account of the outbreak in his work on the disease he called chorea lasciva; and a small set of contemporary letters from observers in nearby cities. The historian John Waller's 2008 monograph A Time to Dance, A Time to Die reproduces and discusses each of these sources in detail [1].

Frau Troffea and the first week

The chronicle accounts agree on the opening of the episode. Verified A woman, identified only as "Frau Troffea" in the surviving records, began to dance in a public street in Strasbourg in the second week of July 1518. The dancing was involuntary in the sense that she did not appear able to stop; observers reported her dancing for several days, sleeping briefly, then resuming. By approximately the fifth day, the chronicles state, between thirty and forty other people had joined her [1][2]. The municipal record does not name them. Specklin's chronicle and other contemporary sources describe the affliction as it spread: dancers continued for days, in some cases for more than a week, some collapsing, some dying. The Specklin chronicle records that "within a month, more than four hundred people were affected" — a figure which most modern historians treat with caution as a likely high estimate but which is the most-cited contemporary number [1][3].

The municipal response

The Strasbourg city council convened in late July or early August 1518 to consider the outbreak. Verified The advice they received from the city's physicians was that the affliction was caused by "hot blood" — an excess of the sanguine humour — and that, on the prevailing humoral medical theory, the only treatment was to allow the dancing to continue to the point of complete exhaustion, when the surplus humour would be discharged. Acting on this advice, the council took the unusual step of allocating municipal resources to facilitate the dancing. The two large guild halls of the city were cleared; the open-air grain market was made available; a wooden stage was erected near the horse fair (the Rossmarkt); and the city hired musicians — flutes, drums, and shawms — to provide music for the dancers, together with paid professional dancers to accompany those whose strength was failing [1][4]. The records of the council expressly authorise these expenditures. The intervention is the most-discussed single feature of the case in the modern literature: the city's authorities, advised by their own physicians, took action that almost certainly worsened the outbreak.

The deaths and the reversal

The number of deaths during the episode is not precisely recorded in any single source. Claimed The chronicler Specklin and a separate Brussels broadsheet account suggest that, at the peak of the outbreak in mid-August, "fifteen people a day" were dying from the dancing, and that the cumulative death toll over the eight weeks of the outbreak ran into "several hundred." The most-cited modern estimate, derived by Waller from the contemporary sources, is in the range of several dozen to several hundred deaths from exhaustion, stroke, and cardiac failure [1][3]. The number is contested; lower-end estimates by other historians have suggested the death toll may have been substantially smaller and that the contemporary chronicles inflated the totals for rhetorical effect. By the end of August, the inadequacy of the "dance it out" approach was apparent. Some time in early September the policy was reversed. The chronicles disagree about the immediate cause: Specklin attributes the reversal to a change of medical advice; the parish records suggest a religious intervention took precedence, with the surviving dancers organised into a pilgrimage to the shrine of St. Vitus in the hills outside the city, where they were offered ritual cures by the local clergy. Music was forbidden in the public squares of Strasbourg. The outbreak abated through September; by the end of the month it was effectively over [1][5].

Paracelsus and the 1526 account

The physician Theophrastus Bombastus von Hohenheim, known as Paracelsus, passed through Strasbourg in 1526 and discussed the 1518 outbreak in his writings on the dancing disease, which he classified as a form of chorea. Verified Paracelsus rejected the humoral explanation that the Strasbourg physicians of 1518 had given. His own classification distinguished three types of dancing affliction: chorea imaginativa (caused by imagination and fixed ideas), chorea lasciva (caused by sensual desire), and chorea naturalis (caused by some natural disturbance of the body) [6]. Paracelsus attributed the Strasbourg outbreak primarily to the first category — an affliction of the imagination, propagating through a community by suggestion and example. His account is the earliest substantial medical commentary on the case and one of the earliest expressions in the European medical literature of what would later be called the psychogenic component of disease. Paracelsus is also the first to associate the Strasbourg episode with the wider European phenomenon of the St. Vitus dance and with the earlier 1374 Rhineland outbreak.

The earlier dancing outbreaks

The 1518 Strasbourg episode is the best-documented but not the first dancing outbreak in northern European history. Verified At least four prior episodes of similar character are recorded in the chronicles of the Rhineland and Low Countries:

• 1374 Aachen / Rhineland. A large-scale outbreak across Aachen, Cologne, Maastricht, Liège, and other cities of the Rhine and Mosel valleys in summer 1374, described in detail by the chronicler Peter of Herental. Thousands of dancers reportedly affected. Contemporary attribution: demonic possession; the affliction was treated by exorcism and pilgrimage to the shrine of St. Vitus.
• 1428 Schaffhausen. A smaller localised outbreak in the Swiss city, several dozen affected.
• Late fifteenth century, various. Sporadic local outbreaks across the Holy Roman Empire and the Low Countries, generally smaller in scale.
• 1518 Strasbourg. The episode of this case file, the largest documented after 1374.

The historical association of the dancing affliction with St. Vitus dates from this period; the saint's name became conventionally attached to involuntary-movement disorders generally, including the neurological condition known today as Sydenham's chorea, which is a distinct medical entity (a sequel of certain streptococcal infections) and not what was happening in Strasbourg in 1518.

The Italian comparison: tarantism

A separate but historically related phenomenon, the southern Italian dancing-cure tradition known as tarantism, is documented from the eleventh century onward and persisted into the twentieth. Verified Tarantism's social form involved supposedly toxic spider bites (in fact rarely actually traceable to spider envenomation) producing a state in which the affected person could be cured only by sustained ritual dancing to specific musical forms (the pizzica, the tarantella). The cultural mechanism is similar: an outbreak of involuntary movement, a socially licensed dancing cure, communal participation. The Italian tradition was a chronic ritualised practice rather than an acute epidemic episode, and the comparison is illuminating without being identical [7].

The competing explanations.

Four explanations are seriously discussed in the modern literature. None is universally accepted.

1. Ergot poisoning

The hypothesis that the dancing plague was caused by ingestion of ergot, the alkaloid-producing fungus Claviceps purpurea which grows on damp rye and produces the ergotamines that are chemically related to LSD, was proposed in its modern form by the American behavioural scientist Linnda R. Caporael in a 1976 paper in Science [8]. Disputed Caporael originally proposed ergot poisoning as an explanation for the 1692 Salem witch trials; the hypothesis was subsequently applied to the medieval dancing plagues by other authors. The argument is that ergot poisoning (ergotism) can produce convulsive symptoms, hallucinations, and involuntary muscular movements; that 1518 Strasbourg sat on rye-growing land; that the summer of 1518 had followed a wet spring conducive to fungal growth; and that an outbreak of ergotism would explain both the involuntary movement and the geographic clustering. The principal objections, articulated in detail by Waller (2008) and others: ergotism normally produces gangrene and a characteristic burning sensation in the limbs (St. Anthony's fire); the dancing plague accounts do not describe these symptoms; ergotism causes contractures and seizures rather than sustained rhythmic movement; ergotism is not generally a community-spreading affliction with the social geography the Strasbourg case shows; and the contemporary chroniclers describe what looks much more like a behavioural state than a toxicological one. The ergot hypothesis retains adherents in popular accounts; it is the minority position in the academic literature [1][8][9].

2. Stress-induced mass psychogenic illness

The currently dominant explanation in the academic literature, most fully developed by John Waller in his 2008 book A Time to Dance, A Time to Die and his subsequent 2009 paper in The Lancet, is that the dancing plague was a mass psychogenic illness — what would today be called a culture-bound conversion disorder — arising in a community under acute and converging stress. Claimed Waller's account assembles the contemporary record of conditions in Strasbourg and the upper Rhine in 1517–1518: a severe famine in the previous year following crop failures and brutally cold winters; outbreaks of smallpox and syphilis in the months preceding July 1518; the religious anxieties of the Reformation period (Strasbourg was in the early years of intense religious upheaval); and a population in which the cult of St. Vitus was deeply established, with a widely held belief that the saint could afflict those who incurred his displeasure with an involuntary dancing curse. Waller's argument is that this combination of physical privation and the specific cultural belief that dancing was a divine punishment created the conditions for a trance-state outbreak: an initial case (Frau Troffea) entering a self-perpetuating altered state which, through socially mediated suggestion, propagated through a vulnerable community. The municipal council's decision to provide stages and musicians, far from helping, supplied the social validation that allowed the affliction to spread further. The 2008 book draws together a substantial body of psychological and historical evidence in support; it remains the leading account [1].

3. The cult of St. Vitus

A related but distinguishable explanation places more weight on the specific religious context: the cult of St. Vitus as both the explanatory framework within which the medieval European community would interpret an involuntary-movement affliction and as the social mechanism that propagated it. Claimed St. Vitus, a fourth-century Sicilian martyr, was venerated across the Holy Roman Empire as the patron saint of dancers and as the divine source of dancing punishments. Shrines to St. Vitus existed across Alsace and the Rhineland, including the shrine to which the Strasbourg dancers were marched at the end of the 1518 outbreak. The argument, advanced by H. C. Erik Midelfort in his 1999 history of madness in early modern Germany and developed by other historians, is that the cult of St. Vitus provided the cultural script that determined what the involuntary affliction would look like, how the community would interpret it, and how it would eventually be terminated (by pilgrimage and ritual cure) [10]. On this view, the cult does not cause the affliction in a clinical sense but rather frames the entire episode: without the cult, the same population pressures might have produced different symptomatic expression.

4. Multiple natural and social factors combined

The mainstream contemporary position among historians of medicine is that no single explanation is sufficient and that the 1518 episode is best understood as a multi-causal event combining (a) genuine physical privation and weakening from famine and disease, (b) a religious-cultural script in which involuntary dancing was an available expression of distress, (c) the social conditions for a trance-state outbreak in a community under prolonged stress, and (d) a municipal policy response that initially amplified rather than damped the outbreak [1][10][11]. This composite view is less satisfying than a single-cause explanation but is what the surviving evidence will support.

The unanswered questions.

The precise initial trigger

What specifically prompted Frau Troffea to begin dancing in mid-July 1518 is not recorded. The chronicles identify her by surname only; her age, station, and the immediate circumstances of her appearance in the street are unknown. Whether her initial episode was a recognisable psychiatric condition expressed within the available cultural script, an acute medical event of a different kind, or a deliberate religious act of penitence cannot be determined from the surviving evidence [1].

The actual number affected and the death toll

The contemporary figures — "four hundred affected within a month," "fifteen deaths a day at peak" — come from a small number of chronicle sources whose reliability for numerical detail is limited. The Strasbourg city council minutes record the policy actions but do not enumerate the dancers or the dead. The cumulative death toll is consequently estimated; the estimates in the modern literature range from "several dozen" to "several hundred" [1][3]. Unverified Whether the lower or higher estimate is correct cannot be settled from the surviving sources.

Why the outbreak ended

The reversal of the municipal policy and the marching of the dancers to the St. Vitus shrine plainly coincided with the end of the outbreak. Whether the ritual intervention itself ended the affliction (as the religious interpretation would have it), or whether the affliction would have ended at approximately the same time regardless (as the medical psychogenic-illness interpretation would have it), is impossible to distinguish on the historical evidence. The structural similarity to other psychogenic-illness outbreaks across history — in which the affliction typically subsides after a period of weeks regardless of intervention — provides some support for the second view, but the case-specific question is not resolvable [1][11]. Disputed

The relationship to the earlier outbreaks

Whether the 1518 Strasbourg outbreak was caused by the same underlying mechanism as the 1374 Aachen / Rhineland outbreak and the smaller earlier episodes — or whether the 1518 case is a culturally similar but mechanistically distinct event — is not determinable on the surviving evidence. The 1374 case is described in such different terms by the contemporary sources (mass possession, large-scale demonic affliction across a wide geographic area) that some historians treat it as a distinct phenomenon. The 1518 case has the additional feature of a specific identified initial patient, the involvement of municipal authority, and a relatively confined geographic footprint, which set it apart from the 1374 episode [1][10].

The absence of subsequent outbreaks in Strasbourg

The 1518 outbreak is, despite its scale, a singular event in Strasbourg's documented history. Verified No comparable outbreak is recorded in the city's chronicles before 1518 or after. The Reformation-era social conditions that Waller and others identify as contributing factors persisted across northern Europe through the sixteenth century without producing additional Strasbourg-scale outbreaks (although smaller episodes are recorded elsewhere). Whether the 1518 episode required a specific conjunction of factors that did not recur, or whether the historical record is simply incomplete, is part of the open question.

Primary material.

The primary record on the 1518 Strasbourg dancing plague is held principally in Strasbourg and southern German archives:

• The Strassburger Stadtrat minutes for July, August, and September 1518, held at the Archives de la Ville et de l'Eurométropole de Strasbourg. The minutes include the council's deliberations and the expenditure authorisations for the guild halls, the stage, the musicians, and the professional dancers.
• The Specklin Chronicle (manuscript, 1530s–1580s; the relevant 1518 entries draw on contemporary materials now lost). Held at the Strasbourg city library (Médiathèque André Malraux) and the Bibliothèque nationale et universitaire de Strasbourg.
• Paracelsus, Opus Paramirum and related writings on chorea, 1526–1530s. Modern editions widely available.
• Parish records of the church of St. Vitus at the Saverne shrine, recording the September 1518 pilgrimage of the surviving dancers.
• A small set of contemporary letters from observers in Brussels, Frankfurt, and other Imperial cities, reporting the Strasbourg outbreak.

The most accessible consolidated discussion of the primary sources is in John Waller's A Time to Dance, A Time to Die (Icon Books, 2008), which reproduces and translates the relevant chronicle passages.

The sequence.

1. 1517–Spring 1518 Severe famine in the upper Rhine following crop failures and harsh winters; outbreaks of smallpox and syphilis in Strasbourg.
2. c. July 14, 1518 Frau Troffea begins dancing alone in a Strasbourg street.
3. Mid-to-late July 1518 Within several days, more than thirty additional residents join the dancing.
4. Late July / early August 1518 Strasbourg city council meets, takes advice from city physicians, attributes the affliction to "hot blood," and resolves to allow the dancing to discharge itself.
5. Early August 1518 Council clears the two principal guild halls and the open-air grain market for the dancers; erects a wooden stage near the horse fair; hires musicians (flutes, drums, shawms) and paid professional dancers.
6. Mid-August 1518 Outbreak at peak: contemporary chronicles report dozens to hundreds of dancers and a substantial daily death rate from exhaustion, stroke, and cardiac failure.
7. Early September 1518 Municipal policy reversed. Music forbidden in public squares. Surviving dancers organised into pilgrimage to the shrine of St. Vitus at Saverne.
8. Late September 1518 Outbreak effectively over.
9. 1526 Paracelsus passes through Strasbourg and incorporates the 1518 episode in his writings on chorea.
10. 1530s Daniel Specklin gathers the contemporary sources into the chronicle that becomes the principal subsequent record.
11. 1976 Linnda R. Caporael publishes the ergot-poisoning hypothesis in Science, applied originally to Salem.
12. 1999 H. C. Erik Midelfort publishes A History of Madness in Sixteenth-Century Germany, developing the cult-of-St.-Vitus interpretation.
13. 2008 John Waller publishes A Time to Dance, A Time to Die, establishing the stress-induced mass psychogenic illness interpretation as the dominant academic position.

Cases on this archive that connect.

The Roanoke Colony (File 015) — a comparable case of a sixteenth-century European population episode whose physical evidence is sparse and whose interpretation depends entirely on the chronicle record that survives.

The Tunguska Event (File 016) — a different kind of "what happened?" file: a documented event with a wide range of competing technical explanations and no scientific consensus on the precise mechanism.

The Carrington Event (File 068) — another historical episode in which contemporary observers documented the event in real time but the underlying physical explanation was not understood until later.

Full bibliography.

1. Waller, John. A Time to Dance, A Time to Die: The Extraordinary Story of the Dancing Plague of 1518. Icon Books, 2008. The standard modern monograph; reproduces the relevant chronicle sources.
2. Specklin, Daniel. Collectanea (manuscript chronicle, sixteenth century). Strasbourg city library (Médiathèque André Malraux).
3. Backman, E. Louis. Religious Dances in the Christian Church and in Popular Medicine. Translated by E. Classen. London: Allen & Unwin, 1952. Early scholarly compilation of the medieval dancing-plague sources.
4. Strassburger Stadtrat minutes for July–September 1518. Archives de la Ville et de l'Eurométropole de Strasbourg.
5. Parish records of St. Vitus shrine, Saverne, September 1518.
6. Paracelsus (Theophrastus Bombastus von Hohenheim). Opus Paramirum (writings on chorea), 1526 onward.
7. De Martino, Ernesto. The Land of Remorse: A Study of Southern Italian Tarantism. Translated by Dorothy Louise Zinn. Free Association Books, 2005 (original Italian 1961).
8. Caporael, Linnda R. "Ergotism: The Satan Loosed in Salem?" Science 192, no. 4234 (1976): 21–26. Original ergot-poisoning hypothesis.
9. Bartholomew, Robert E. "Ergotism, Tarantism and Mass Psychogenic Illness: Distinguishing the Strasbourg Dance of 1518." Journal of Nervous and Mental Disease 199, no. 1 (2011): 70–72.
10. Midelfort, H. C. Erik. A History of Madness in Sixteenth-Century Germany. Stanford University Press, 1999.
11. Waller, John. "A Forgotten Plague: Making Sense of Dancing Mania." The Lancet 373, no. 9664 (2009): 624–625.
12. Hecker, Justus Friedrich Karl. Die Tanzwuth, eine Volkskrankheit im Mittelalter. Berlin, 1832. The first modern scholarly study of the dancing plagues; English translation as The Dancing Mania.