The inhabitants of the principality were also free from having to pay taxes or render services to the Crown, and could not be conscripted into the armed forces, although they did remain subject to the requirements of the Roman Catholic Church.
[5] Among their many acts was the construction of the present Château de Sully-sur-Loire, which would become the seat of the Lords of Sully, successors of Marie through her first marriage to Guy.
In about 1396, Guy participated in the crusade with John the Fearless, later to become Duke of Burgundy upon his father’s death in 1404, as part of the forces sent to assist King Sigismund of Hungary in his war against the Sultan Bayezid I.
Charles would go on to become co-commander of the French army at the Battle of Agincourt on 25 October 1415, where he was slain in combat against the English forces led by King Henry V. Before Charles’ death in battle, Princess Marie died in Pau, Kingdom of Navarre, between 6 September 1409 and 17 February 1410, the date in which an inventory of her furniture and goods was made.
Aside from her rule as Princess of Boisbelle, Marie was also Countess of Guînes, Baroness of Sully, Baroness of Craon, Lady of La Chapelle-d'Angillon and des Aix-Dam-Gilon, of Saint-Gondon, of Châteaumeillant, of Bruère, of Épineuil, of Corberin, of Sainte-Hermine, of Prahecq, of Lussac, of Champagne, of Bois de Chisay, of Montrond, of Argent, of Clémont, of Villebon, of Orval, of Dun-Le-Roi, and of Châlucet.