A third common element is the presence of witnesses. Since these are based on true stories, there are usually people around who see the strange happenings. These witnesses then spread the story, which contributes to the idea of demonic possession. In the Loudun possessions, the nuns' strange behaviors were witnessed by other nuns, the local community, and even some clergy members.
In my opinion, most of the so - called real life demonic possession stories are not what they seem. There are a lot of superstitions involved. Take the case of a person acting erratically. In the past, they might be labeled as possessed. But now we know that things like drug use, brain damage, or mental illness can cause such behaviors. However, there are some cases that are hard to explain away completely. Some people who have gone through exorcisms claim to be cured, but it could be the power of suggestion or a placebo effect.
The Loudun possessions in France in the 17th century are also based on a true story. A group of nuns in a convent in Loudun started showing extreme behaviors. They would scream, contort their bodies, and make lewd remarks. It was believed at the time to be demonic possession. But looking back, there could have been many factors at play. It could have been mass hysteria, or perhaps the strict and repressive environment of the convent led to some sort of psychological breakdown among the nuns. There were also political and religious motives involved as some used the situation to target certain individuals.
Yes. The movie draws inspiration from some accounts that were thought to be true. However, in the process of making it into a film, a lot of creative liberties were taken. For example, the way the possession is shown in the movie might be more dramatized than what was originally reported in the real - life events it was based on. But overall, it has its roots in a true story.