King Eric XIV of Sweden. Guy was so crazy that he got dethroned and later poisoned. Before that he murdered 5 other Swedish nobles out of paranoia.
King Henry VIII out of obvious reasons.
Duke Ulrich of Württemberg. Wanted to establish a South German kingdom. After marrying the Bavarian princess to form a personal union between the two states (good idea) he besieged the free city of Ulm (very bad idea) so the Emperor came after him to keep the peace within the Empire and also to prevent another big nation from forming before his doorstep. Ulrich had to flee into exile, thus nearly ruining every accomplishment of Eberhard I. and almost getting Württemberg annexed by Habsburg-Austria. Died in 1550 and now gets called the Swabian Henry VIII.
King Charles II of Spain. Self-explanatory.
Phil Ochs. Protest singer who became a shizo after getting chocked in Africa during a robbery, believed the CIA, FBI, etc. were after him. Hanged himself in 1976.