Beginning in 982 the Sargans region was part of the lands of the Counts of Bregenz. In 1160, the male line of the Counts of Bregenz died out. Count palatine Hugo of Türbingen inherited most of their lands, through his wife Elisabeth. His son, Hugo, inherited the Bregenz lands around Lake Constance, including Sargans. This Hugo, who adopted the name Montfort und Werdenberg built or expanded Sargans Castle before his death in 1228. Excavations around the oldest part of the castle show that there was an earlier fort or castle, but nothing is known about that building. Hugo built the large bergfried, expanded the walls to the west and may have built a palas on that side of the castle.
In the mid-13th century the Montfort und Werdenberg lands were divided between Hugo of Werdenberg-Heiligenberg and his brother Hartmann of Werdenberg-Sargans. Hartmann took up residence in the castle and probably expanded the palas. The castle was first mentioned in 1282. Over the following century the wealth and lands of the Counts of Werdenberg-Sargans were divided over and over again between descendants. By the last 14th century, Count Johann I ruled over a small and poor county under the Habsburgs. In the Battle of Näfels in 1388, the count commanded a wing of the Austrian army that was supposed to cross the Kerenzerberg Pass. However, when he saw the threatened destruction of the main Austrian army, he fled back over the pass. The cost of the war, as well as other expenses forced Johann I to sell the castle and village to Leopold of Austria.References:
The Château de Chaumont was founded in the 10th century by Odo I, Count of Blois. The purpose was to protect his lands from attacks from his feudal rivals, Fulk Nerra, Count of Anjou. On his behalf the Norman Gelduin received it, improved it and held it as his own. His great-niece Denise de Fougère, having married Sulpice d'Amboise, passed the château into the Amboise family for five centuries.
Pierre d'Amboise unsuccessfully rebelled against King Louis XI and his property was confiscated, and the castle was dismantled on royal order in 1465. It was later rebuilt by Charles I d'Amboise from 1465–1475 and then finished by his son, Charles II d'Amboise de Chaumont from 1498–1510, with help from his uncle, Cardinal Georges d'Amboise; some Renaissance features were to be seen in buildings that retained their overall medieval appearance. The château was acquired by Catherine de Medici in 1550. There she entertained numerous astrologers, among them Nostradamus. When her husband, Henry II, died in 1559 she forced his mistress, Diane de Poitiers, to exchange Château de Chaumont for Château de Chenonceau which Henry had given to de Poitiers. Diane de Poitiers only lived at Chaumont for a short while.
Later Chaumont has changed hands several times. Paul de Beauvilliers bought the château in 1699, modernized some of its interiors and decorated it with sufficient grandeur to house the duc d'Anjou on his way to become king of Spain in 1700. Monsieur Bertin demolished the north wing to open the house towards the river view in the modern fashion.
In 1750, Jacques-Donatien Le Ray purchased the castle as a country home where he established a glassmaking and pottery factory. He was considered the French "Father of the American Revolution" because he loved America. However, in 1789, the new French Revolutionary Government seized Le Ray's assets, including his beloved Château de Chaumont.
The castle has been classified as a Monument historique since 1840 by the French Ministry of Culture. The Château de Chaumont is currently a museum and every year hosts a Garden Festival from April to October where contemporary garden designers display their work in an English-style garden.