I'm working on a medieval fantasy and one of the characters is a prince who is suffering from schizophrenia. My question is how would this disease present in a medieval world?
I imagine it might be interpreted as some variety of visions, possession by demons or spirits, or a curse. Schizophrenia has a lot of potential symptoms, and which ones manifest in the prince will likely determine what it is believed to be. How common such a condition is, and any prior occurrences within his family will also affect the interpretation.