What caused the deadly 'dancing plague' of 1518?

The dancing plague began in July 1518 when a woman named Frau Troffea stepped out of her home and began to dance fervently in the streets of Strasbourg.

According to contemporary accounts, Troffea danced for hours, ignoring the pleas of her husband and neighbors to stop.

Within a week, 30 other individuals in the city also began to dance, and before long, the epidemic had spread to 400 people.

Many dancers were unable to stop for days, even weeks, and could only be stopped by exhaustion or collapse.

The first hypothesis proposed to explain the dancing plague was that it was caused by mass hysteria or a psychological disorder.

At the time, Strasbourg was a densely populated and highly stressed city, with frequent outbreaks of disease, famine, and social unrest.

Some historians have suggested that the dancing may have been a form of mass psychogenic illness, triggered by anxiety, religious fervor, or other psychological factors.

However, this theory fails to explain why only a small fraction of the population was affected and why the dancers exhibited such similar symptoms.

Another theory suggests that the dancing plague was caused by a toxic or hallucinogenic substance, such as ergot fungus.

Ergot is a mold that grows on rye and other grains and can produce compounds that cause delirium, convulsions, and hallucinations.

The fungus was known to have caused outbreaks of ergotism, or St. Anthony's fire, in medieval Europe, which manifested as a range of symptoms, including fever, seizures, and hallucinations.

Some researchers have suggested that the dancers may have consumed bread or other food contaminated with ergot, which could have triggered the convulsions and the compulsion to dance.

A third theory proposes that the dancing plague was a form of mass ritual or protest.

Strasbourg was a religiously diverse city, with a mix of Catholics and Protestants, and tensions were high between the two groups.

Some historians have suggested that the dancing may have been a form of ecstatic religious experience or a protest against social and religious hierarchies.

Others have speculated that the dancers may have been members of a secret society or cult, who used the dancing as a form of initiation or religious ceremony.

Despite extensive research and speculation, the true causes of the dancing plague remain unknown.

However, the event has had a lasting impact on culture and science, inspiring works of art, literature, and music, as well as scientific investigations into the nature of mass psychogenic illness and the effects of toxic substances on the human body.

Today, the dancing plague of 1518 remains one of the most bizarre and enigmatic events in history, a testament to the strange and unpredictable ways in which human behavior can manifest.