Lord Prestimion: Book Two of The Prestimion Trilogy (The Majipoor Cycle)

New to the power and title of Coronal, Lord Prestimion finds his world shattered, in the grip of chaos and panic. As a final "gift", the rebels led by Dantirya Sambail have left the world with a fastspreading plague of madness, caused by their sorcerous treason. Now Prestimion must work to rebuild his broken world, to track down Sambail before the slow-creeping despair that infects humanity can destroy him and the world he rules.