The castle had two lives... oh, yes! One in the Renaissance era, the other one in the 19th century... Well, Chantilly was the fief of Rothold de Senlis, lord of Ermenonville in the 10th century, then of Bouteiller de Senlis and Orgemont families in the Middle-Ages.
Then the castle fell to the famous constable Anne de Montmorency in 1528. This one razed the old fortress and raised his own house, based on Pierre de Chambiges' plans... after that he added the Petit château ("Small castle") in 1560, created by Jean Bullant... oh, yes, the famous architect who raised Ecouen castle, for our constable de Montmorency!
This was Chantilly's first life. Let's see now the second one! The castle fell to the Condé in 1643, who added beautiful stables between 1719 and 1735. I said beautiful, but... it's more "magnificent"!
Just imagine that Louis-Henri of Bourbon, prince de Condé, thought that when he died, he would be reincarnate as a horse! So, he raised stables like a real palace! Well... duke of Aumale, who inherited the vast domain, entirely refit out the apartments in Louis XV and Louis XVI style.