How did Anneliese get possessed?

Anneliese Michel, a German woman, was believed to be possessed after experiencing severe psychological and physical symptoms, including auditory hallucinations and seizures, which her family interpreted as demonic possession. Despite undergoing psychiatric treatment, her condition worsened, leading her devoutly religious parents and two priests to pursue an exorcism. They believed that Anneliese was tormented by demons, and after a series of exorcisms in 1975, she tragically died from malnutrition and dehydration. Her case raised significant controversy regarding mental health treatment and the intersection of faith and medicine.