The Château de Chaumont (French: [ʃɑto də ʃomɔ̃]; or Château de Chaumont-sur-Loire) is a castle in Chaumont-sur-Loire, Loir-et-Cher, France. The castle was founded in the 10th century by Odo I, Count of Blois. After Pierre d'Amboise rebelled against Louis XI, the king ordered the castle's destruction. Later in the 15th century Château de Chaumont was rebuilt by Charles I d'Amboise. Protected as a monument historique since 1840, the château was given into state ownership in 1938 and is now open to the public.