The Prince and Princess de Broglie, the last private owners of the castle,
introduced an extraordinary sense of modernity, fantasy and high society to the estate.
In 1875, Marie-Charlotte de Broglie and her husband, Henri-Amédée de Broglie, gained ownership of the château.
The architect Paul-Ernest Sanson was hired for the complete restoration of the château,
while the architect Marcel Boille was responsible for building the estate's model farm.
Unfortunately, a turn of fortune forced the de Broglie family to sell Chaumont to the state in 1938.
It was then registered as a historical monument.