How a witch-hunting manual and social media helped spark Europe’s witch craze

The sudden emergence of witch trials in early modern Europe may have been fueled by one of humanity’s most important intellectual milestones: the invention of the printing press in 1450.

A new study in Theory and society shows that the printing of witch-hunting manuals, notably that of the Malleus maleficarum in 1487, played a crucial role in the spread of persecution across Europe. The study also highlights how trials in one city influenced others. This social influence – observing what neighbors were doing – played a key role in whether a town adopted witch trials.

“Cities were not making these decisions in isolation,” said Kerice Doten-Snitker, a postdoctoral complexity researcher at the Santa Fe Institute and lead author of the study.

“They observed what their neighbors were doing and learned from those examples. The combination of new ideas from books and the influence of nearby trials created the perfect conditions for these persecutions to spread.”

The witch hunt in Central Europe began in the late 15th century and lasted for almost 300 years, resulting in the prosecution of around 90,000 people and almost 45,000 executions. Belief in witches and sorcery had been present in European culture for centuries, but the level of systematic and widespread persecution that occurred during this period was unprecedented.

According to Doten-Snitker, the advent of printing allowed the rapid spread of ideas about witchcraft that had previously been confined to small intellectual circles, such as religious scholars and local inquisitors. The most infamous of these publications, the Malleus maleficarum, was both a theoretical and practical guide to identifying, interrogating, and prosecuting witches. Doten-Snitker explains that once these manuals were put into circulation, they provided a framework for how local authorities could deal with suspicions of witchcraft in their communities.

For their study, Doten-Snitker and colleagues build on previous research by looking beyond broad economic and environmental factors and focusing on how new ideas about witchcraft spread through social media and sales, influencing behavior in a slow but powerful way.

They analyzed data on the timing of witch trials and the publication of witch-hunting manuals from 553 central European towns between 1400 and 1679, when there was a notable reduction in frequency and intensity of persecution. Their results suggest that the publication of each new edition of the Malleus maleficarum was followed by an increase in witch trials. However, it wasn’t just proximity to a printing press that determined whether a town would conduct trials; the influence of neighboring towns played an equally important role.

When one city adopted the practices described in the Malleus maleficarum, neighboring cities often followed suit, learning from each other. This process, which Doten-Snitker and his co-authors call diffusion of ideas, often took many years, as city residents needed time to digest new ideas about witchcraft and transform them into behaviors. However, once it took hold, it created a slow but powerful ripple effect that spread across the continent.

Although the research focuses on historical witch trials, Doten-Snitker sees clear modern parallels for how large-scale social change occurs.

“The process of passing the witch trials is not unlike the way modern governments adopt new policies today,” Doten-Snitker said. “It often starts with a change in ideas, which is reinforced through social media. Over time, these ideas take root and change the behavior of entire societies.”