His sisters were Anne Élisabeth Laurence de Montmorency (wife of Théodore, Prince of Bauffremont, son of Alexandre de Bauffremont) and Anne Louise Charlotte Alix de Montmorency (wife of Napoléon Louis, 3rd Duke of Talleyrand-Périgord, de jure 3rd Duke of Dino).
[2] He served as aide-de-camp to Marshal Louis-Nicolas Davout as well as chamberlain to Emperor Napoleon in 1813.
[3] From 1815 to 1820, he was aide-de-camp to the Duke of Orléans (later King Louis Philippe I).
The dukedom passed to his nephew, Nicolas Raoul Adalbert de Talleyrand-Périgord, the youngest son of his sister Anne Louise Charlotte Alix de Montmorency.
Her elder son, Boson de Talleyrand-Périgord, inherited the dukedom of Talleyrand.