The Comte de Brienne was naturally destined to public office. He traveled to Germany, Poland and Italy, by order of his father, the last as well prepare for his career. He was back in Paris towards the end of 1609, that he was noticed by Henry IV, who allowed him to attend the board sometimes. Marie de Medici, regent of France, commissioned him in 1614 to negotiate with some members of the États généraux, "whose minds were unwell", and his clever response obtained from them the nomination of a president acceptable to the court. This success earned him in 1617, master of ceremonies and provost of King's orders. Until the death of his father, his principal occupation "was to accompany the King and gain the honor of his good graces, to which he succeeds."