After Henry became the legitimate heir to the throne of France in 1589, Roquelaure followed him in all his battles to secure the crown: Coutras, Arques and Ivry. As a Catholic, Roquelaure played an important role in convincing Henry to adopt that faith to strengthen his hold on the French crown. His service gained him many charges and benefices which turned him into one of the most important persons of the kingdom. He was made master of the wardrobe in 1589, a knight of the Order of the Holy Spirit and lieutenant-general of Upper Auvergne, captain of the Palace of Fontainebleau, and later governor of the County of Foix, lieutenant-general of Guyenne in 1597 and mayor of Bordeaux.