Henri-Auguste de Loménie (1594 – 3 November 1666), Count of Brienne, Seigneur de La Ville-aux-Clercs was a French politician. He was secretary of state for the navy from 1615 to February 1643, and then secretary of state for foreign affairs from 1643 to 1663 under Mazarin during the minority of Louis XIV. From the Loménie family (originating in Flavignac in Limousin), he was the son of Antoine de Loménie, secretary of state to Henry IV and a Huguenot convert.
The Count 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."
The British Embassy, where he was responsible for negotiating the marriage of Henrietta Maria of France with the Charles I of England. However, when he seemed to have met with success in its attempt at accommodatation, he was disowned by Louis XIII and Richelieu.
The kindness of the queen mother of Louis XI to him was also the affection of the princess to Madame de Brienne, his wife, whom the whole court knew to be the closest confidante of Anne of Austria. This influence kept him in power until the death of Mazarin, but before that time, his influence began to wane.
The impairment of the Count of Brienne was not soon enough for the young and voluntary authority of Louis XIV; high diplomatic capacities should preferably also attract the attention of the king, a great kingdom was coming, and he had to carry and moderate both the ideas of the gigantic new prince, physical strength and moral well above that of the Count de Brienne. Hugues de Lyonne was charged in 1663, with the Department of Foreign Affairs, replacing him. He died in 1666.