Now, new research has indicated the answer – some were buried face-down as survivors feared the corpse.
Going back to the records, the team found that many people had been face-patting over the past 900 years, mainly in Central Europe such as Germany, Switzerland and Austria.
The team believes the practice was originally intended to show humanity’s humility towards God.
But, in the 1300s, Emily Alterges of the Institute of Forensic Medicine of the University of Bern in Switzerland noted “some changes”.
By analyzing medieval folklore, the authors of the study, published in PLOS One, found the stories of Natchezhar, loosely translated as devotees of zombies – or zombies to be more specific.
Before the 1300s, dead or ghosts were considered a friendly presence.
But when the plague swept across Europe in the 1300s, nearly half of the population died, the people at the time felt it was a punishment for God.
Bodies would be built on the road as civilization struggled to cope with the death rate and humanity was being punished with fear, the perception of the dead changed and people became fearful.
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“There was a theory that if someone was the first person in the community to die during an epidemic, one would become a nachzer.”
With little information about the plague at the time, people felt that they were being damned at the funeral of their loved ones as many more would die soon after the funeral.
Matthias Toplak, an archaeologist at the University of Tubingen in Germany who was not involved in the study, also told National Geographic: “This change in evil spirits occurs around 1300 or 1400.
“The background of all these supernatural beliefs should be the sudden death of many individuals of a society.
“It is understandable that people blamed supernatural spirits and took measures to prevent the dead from returning.”