Prince Joseph was born on 9 October 1836 at the Château de Menars in France.

[1] From his mother's first marriage, he had an elder half-brother, Henri, Marquis of Brigode who was the Mayor of Romilly (and married Annette du Hallay-Coëtquen).

His maternal grandparents were Françoise-Marie LeRoy and a wealthy financier Henri de Pellapra, though Émilie claimed to be a daughter of Napoleon.

A member of the Catholic Party, he later served as the governor of the province of Hainaut from 1870 to 1878 and Foreign Minister of Belgium from 1884 until his death in 1892.

[1] The Prince de Chimay died on 29 March 1892 in Brussels,[23] and was succeeded in his title by his eldest son, Joseph.