Ergot and Witchcraft Theories: Did a Fungus Cause Witch Trials?

Ergot is a fungus (Claviceps purpurea) that infects rye and other grains, and the poisoning it causes, ergotism, produced terrible epidemics in medieval and early modern Europe known as St Anthony's fire. Since the 1970s several writers have argued that ergot poisoning explains the fits and visions behind the Salem witch trials and other witch-hunts; the idea is popular and memorable, but most historians of witchcraft reject it as an explanation for the trials, which they attribute to religious, legal and social causes.

Ergot and Ergotism: St Anthony's Fire§

When Claviceps purpurea infects a cereal head, it replaces some of the grains with hard, dark, curved bodies called sclerotia. Their resemblance to a cockerel's spur gave the fungus its French name, ergot. The sclerotia contain a family of alkaloids that constrict blood vessels and act on the nervous system, and in years of cold, wet weather when rye was heavily infected, bread made from contaminated grain could poison whole communities. Rye, the staple of poorer people in much of northern and eastern Europe, was the grain most often affected.

Medieval chroniclers recorded outbreaks of a burning disease that consumed limbs, often called "holy fire" or "St Anthony's fire." An entry in the Annals of Xanten for 857 is frequently cited as the earliest European description, and a severe epidemic struck Aquitaine in 994, though modern historians caution that not every "fire" in the chronicles was ergotism. Two forms are now distinguished. Gangrenous ergotism cuts off circulation to the extremities, which become cold, black and may detach. Convulsive ergotism produces muscle spasms and seizures, painful tingling and the feeling of insects crawling beneath the skin, and in some reports delirium and visions. The link between the disease and spurred rye was recognised by French physicians in the seventeenth century, and improvements in agriculture and grain cleaning later made epidemics rare.

The Order of St Anthony and the Isenheim Altarpiece§

The religious response to ergotism shaped European art. Around 1095 a confraternity was founded at La Motte in the Dauphiné, where relics of St Anthony the Great, the Egyptian desert father, were venerated, to care for pilgrims suffering from the burning sickness. It became the Order of Hospitallers of St Anthony, the Antonines, whose houses across Europe received the afflicted, offered them better bread and wine from the order's estates, and in some cases amputated gangrenous limbs. The Antonines' emblem was the tau cross, and their pigs, wearing bells, were allowed to roam freely in many medieval towns.

Between about 1512 and 1516 Matthias Grünewald painted his great altarpiece for the Antonine preceptory at Isenheim in Alsace, now in the Unterlinden Museum in Colmar. Patients were brought before it in the hope of healing. Its crucified Christ is covered in sores, and in the panel of the Temptation of St Anthony a figure with a swollen belly and ulcerated skin lies in the corner; art historians have often read these as images of the diseases, including ergotism, that the hospital treated.

Caporael and the Salem Hypothesis§

The modern ergot theory of witchcraft began with an article by the psychologist Linnda Caporael, "Ergotism: The Satan Loosed in Salem?", published in the journal Science in 1976. Caporael pointed to the symptoms recorded among the afflicted girls of Salem Village in 1692: fits, contortions, sensations of being pinched and pricked, and visions of spectres. She argued that these matched convulsive ergotism, that rye was grown in the village, and that the weather of 1691 could have favoured the fungus.

The reply came quickly. Later in 1976 Nicholas Spanos and Jack Gottlieb published a detailed rebuttal in the same journal. They noted that convulsive ergotism typically struck whole households, especially young children, and came with severe hunger, digestive symptoms and lasting damage, none of which appears in the Salem records; that the afflicted girls' fits started and stopped in response to the accused in the courtroom; and that the crisis ended when the authorities ceased to credit spectral evidence, not with a change of harvest. Historians of Salem, from Paul Boyer and Stephen Nissenbaum's study of village factions to Mary Beth Norton's account of frontier war with the Wabanaki, have explained the events through social, religious and political pressures. The ergot hypothesis survives mainly in popular culture and television documentaries.

Matossian, Rye and the Witch-Hunts of Europe§

The historian Mary Kilbourne Matossian broadened the argument in Poisons of the Past (1989). She correlated cold, damp years, rye consumption and outbreaks of collective disturbance in early modern Europe, suggesting that ergot and other moulds help explain not only some witch-hunts but also events such as the rural panic of 1789 in France, the "Great Fear." The Italian historian Piero Camporesi's Bread of Dreams, written from a different perspective, described a world in which hunger, adulterated bread and plants mixed into flour gave the poor a near-permanent state of dazed, visionary misery.

Specialists in the European witch trials have generally found these arguments unconvincing as explanations of prosecutions. Trials depended on demonological theory such as that of the Malleus Maleficarum, on judicial procedures including torture, on neighbourly conflict and on the politics of particular jurisdictions, and many intense hunts took place in regions and years that do not fit the rye-and-weather pattern. Ergot may have contributed to individual episodes of illness interpreted as bewitchment or possession, but the witch-hunts were made by courts, not by grain.

Dancing Plagues, Pont-Saint-Esprit and Other Outbreaks§

Ergot is regularly proposed for other strange episodes. The dancing epidemic of Strasbourg in 1518, when dozens of people danced uncontrollably for days, and earlier outbreaks along the Rhine in 1374, have been attributed to it; the historian John Waller argues instead for a mass psychogenic illness shaped by local belief in St Vitus, since ergot poisoning causes convulsions and gangrene, not coordinated dancing.

In August 1951 the French town of Pont-Saint-Esprit suffered an outbreak of poisoning traced to bread from a local bakery: hundreds fell ill, many with hallucinations and agitation, several died and some were confined to psychiatric hospitals. The journalist John G. Fuller's The Day of St. Anthony's Fire (1968) popularised the ergot explanation, but investigators also proposed an organic mercury fungicide or a chemical flour bleach, and the cause remains disputed.

Ergot, LSD and the Eleusis Question§

Ergot also had a place in medicine. Early modern midwives used it to hasten childbirth, a dangerous practice, and its alkaloids were later refined into drugs for haemorrhage and migraine. In 1938, working on ergot derivatives at Sandoz in Basel, the chemist Albert Hofmann synthesised lysergic acid diethylamide, LSD, and discovered its psychoactive effects in 1943.

This connection led Hofmann, R. Gordon Wasson and the classicist Carl Ruck to propose in The Road to Eleusis (1978) that the kykeon drunk in the Eleusinian Mysteries contained an ergot preparation from barley. The theory is discussed in the guide to entheogens and sacred plants; classicists remain divided, and archaeological support is limited. Similar suggestions have been made that ergot, like the plants of the flying ointments and the witch's garden, lies behind visions of the sabbath. Ergot is a dangerous poison, and this history is no guide to any use of it.

Frequently asked questions§

Did ergot cause the Salem witch trials?§

Most historians think not. Linnda Caporael proposed the idea in 1976, but the symptoms at Salem do not match ergotism well, the afflictions followed the courtroom rather than the harvest, and social and religious explanations account for the crisis more fully.

What is St Anthony's fire?§

St Anthony's fire was a medieval name for ergotism, the poisoning caused by eating grain infected with ergot. It was named after St Anthony the Great, whose relics and hospital order were associated with its sufferers.

Is ergot related to LSD?§

Yes. Albert Hofmann first synthesised LSD in 1938 from lysergic acid, a compound derived from ergot alkaloids. Ergot itself, however, is a toxic mixture that causes gangrene and convulsions.

Why is ergot linked with witches?§

Because convulsive ergotism can cause fits and visions that early modern people might have read as bewitchment or possession. Writers since the 1970s have used this to explain witch trials, but the theory remains a minority view among historians.

Sources and further reading§

• The Day of St. Anthony's Fire — John G. Fuller, 1968
• Salem Possessed: The Social Origins of Witchcraft — Paul Boyer & Stephen Nissenbaum, 1974
• The Road to Eleusis: Unveiling the Secret of the Mysteries — R. Gordon Wasson, Albert Hofmann & Carl A. P. Ruck, 1978
• LSD: My Problem Child — Albert Hofmann, 1980
• Poisons of the Past: Molds, Epidemics, and History — Mary Kilbourne Matossian, 1989
• Bread of Dreams: Food and Fantasy in Early Modern Europe — Piero Camporesi, 1989
• In the Devil's Snare: The Salem Witchcraft Crisis of 1692 — Mary Beth Norton, 2002
• A Time to Dance, a Time to Die: The Extraordinary Story of the Dancing Plague of 1518 — John Waller, 2008