The initial castle of Lord Evrard II de La Marck was built from 1424 onwards around an existing Benedictine priory. The small independent principality of Sedan was not recognised until the middle of the 16th century, but Evrard’s descendants – eight princes and a princess – would continuously expand and reinforce the castle in the following centuries. A new princely dwelling appeared during the Renaissance, the walls were thickened and four huge bastions were added. In 1642, after the cession of the principality to King Louis XIII, the fortress turned into barracks for the French army.