Henry Iv by Luigi Pirandello

In this novel, the protagonist is a man who, after an accident during a historical pageant, comes to believe himself to be the medieval German emperor Henry IV. For twenty years, he lives in a villa with attendants who indulge his delusion. The story delves into themes of madness, reality, and illusion as characters from his past attempt to cure him, leading to a complex examination of the nature of sanity and the role that personal mythologies play in our lives. As the line between the protagonist's delusion and the reality of those around him blurs, the narrative raises profound questions about the nature of identity and the masks people wear in society. The 10966th greatest book of all time