Burmese folk religion
These exorcists, or "ahletan hsaya", are said to possess powers that can fend away or challenge these evil demons. These exorcists were often seen as very holy, because they had to be to combat troublesome spirits. They attempt exorcisms by giving the nat offerings. As an interesting overlap with Buddhism, exorcisms can be performed by holding the Buddha up to the possessed person, in an effort to have the Nat flee. If the exorcist cannot banish this spirit alone, they often ask for the assistance of the nat-kadaw. Sorcerers, or "weikzas" also harnessed the power of these nats through many complex rituals, to gain their own supernatural powers.
The Exorcist (novel)
Recent investigative research by freelance journalist Mark Opsasnick indicates that Blatty's novel was based on an actual 1949 exorcism of a young boy from Cottage City, Maryland, whom Opsasnick refers to using the pseudonyms Robbie Mannheim and Roland Doe. The boy was sent to his relative's home on Roanoke Drive in St. Louis where most of the exorcism took place.