1778: Inspired by the gardens, Jean-Jacques Rousseau spends 6 weeks in Ermenonvillle in complete serenity. He passed away on the 2nd of July 1778, and René de Girardin has him buried in the isle of poplars.

1880: Ermenonville castle is sold to Prince Radziwill by Giraradin’s heirs.

1927: Death of Léon Radziwill and dissolution of the estate. Au Midi park is sold to the Touring Club de France and is renamed: Jean Jacques Rousseau park.

1942: The castle and North park are sold to Ettore Bugatti.

1964: Hispano-Suiza buy the Bugatti factory and put the castle on the market, it is bought by a financial company. The castle goes through various stages: retirement home, restaurant and cult headquarters.

1991: To the great pleasure of clients and inhabitants attached to the castle, the “Les Hôtels Particuliers” group become owners and manages it in full respect of its history.