I know a little bit about this place through research into Weave a Garland of My Vows.
Marie de Rohan was a great friend of César and his brother Alexandre, the bastard sons of Henri Quatre.
All three of them hated Richelieu.
Marie wrote : I think I am destined to be the object of the folly of madmen’ – Marie de Rohan 1600-1679 (I vibe with that!!)
She was implicated in the downfall of de Chalais and went to Richelieu to plead for this man’s life but the Cardinal ignored her.
de Chalais was executed by a fellow prisoner who was granted a full pardon if he beheaded this man. The new executioner only had an adze and it took thirty blows to do the dirty deed.
César was involved in many noble intrigues during the reign of his half-brother Louis XIII of France. Implicated in the conspiracy of Chalais against Cardinal Richelieu, he and his brother Alexandre, the Chevalier de Vendôme, were imprisoned in the Château de Vincennes in 1626. He was released in 1630.
Apparently Ms Rowlingpin has connections to Vincennes as well.
You Does She Think She Is?