This is a list of monarchs who have been described as mentally ill
in some way by historians past or present.
In many cases, it is difficult to ascertain whether a given historical monarch did in fact possess a genuine mental illness of some sort, whether he or she was merely eccentric or suffering symptoms of a physical illness, or whether he or she was just disliked by chroniclers.
- King Charles II of Spain (November 6, 1661, Madrid - November 1, 1700, Madrid) Charles II is known in Spanish history as El Hechizado ("The Bewitched") from the popular belief — to which Charles himself subscribed — that his physical and mental disabilities were caused by "sorcery" rather than the much more likely cause: centuries of inbreeding within the Habsburg dynasty (in which first cousin and uncle/niece matches were commonly used to preserve a prosperous family's hold on its multifarious territories). Charles' own immediate pedigree was exceptionally populated with nieces giving birth to children of their uncles: Charles' mother was niece of Charles' father, being daughter of Maria Anna of Spain (1606-46) and Emperor Ferdinand III. Thus, Empress Maria Anna was simultaneously his aunt and grandmother. Still, the king was exorcised, and the exorcists of the kingdom were called upon to put straight questions to the devils they cast out. His great-great-great grandmother, Joanna the Mad, mother of the Spanish King Charles I who was also Holy Roman Emperor Charles V — became completely insane early in life; the fear of a taint of insanity ran through the Habsburgs. Charles descended from Joanna a total of 14 times — twice as a great-great-great grandson, and 12 times further.
Charles II was the last of the Spanish Habsburg dynasty, physically disabled, mentally retarded and disfigured (possibly through affliction with mandibular prognathism — he was unable to chew). His tongue was so large that his speech could barely be understood, and he frequently drooled. He may also have suffered from the bone disease acromegaly.