An interesting Wiki piece about Chantilly. I like the built/destroyed/rebuilt bit –
The original mansion was destroyed in the French Revolution. It was repaired in a modest way by Louis Henri II, Prince of Condé, but the entire property was confiscated from the Orléans family, between 1853 and 1872, during which interval it was owned by Coutts, an English bank. Chantilly was entirely rebuilt, between 1875 and 1882, by Henri d’Orléans, duc d’Aumale (1822–1897) to the designs of Honore Daumet. The new château met with mixed reviews. Boni de Castellane summed up one line of thought: “What is today styled a marvel is one of the saddest specimens of the architecture of our era — one enters at the second floor and descends to the salons”. In the end, the Duc d’Aumale bequeathed the property to the Institut de France upon his death in 1897.
Well because of the House of Montmorency who owned this place in the 15th/16th/17th cc.
Until 1632, in fact, when Henri, Duc de Montmorency was beheaded for rebelling against Louis XIII.
The Montmorency were governors of the Languedoc for centuries, and the Languedoc was the heart of the Cathar religion.
Self-reference from March this years : Hidden History of the Cathars
When Henri was executed, Chantilly was inherited by his sister, Charlotte who happened to be married to Henri, Prince de Condé (1588–1646) heir presumptive to the French throne until 1601 when Louis XIII was born.
So, along with all of the Languedoc, the crown came into possession of one of the most beautiful palaces in France.