A Colonel d'État-Major of the National Guard, he supported the coup d'état of 2 December 1851. Made a free member of the Académie des Beaux-Arts on 19 November 1853, on 5 July 1853 he became intendant des Beaux-Arts of the Emperor's Household and finally in 1870 surintendant of the Imperial Museums. Until the fall of the Second French Empire, he played a highly important rôle, acting as a kind of minister of cultural affairs. It was at his request that the painter William Wyld (of English birth but resident in Paris) was allowed to exhibit in the French section of the 1855 Exposition Universelle (the second after that in London in 1851). He was responsible for four museums (Louvre, Luxembourg, Versailles, then the Saint-Germain-en-Laye), for the objets d'art in the imperial palaces, for imperial commissions of paintings, sculptures and engravings and for the organisation of the Paris Salon. With difficulty, he also reformed the École des Beaux-Arts. He also became a senator and conseiller général for the Aisne. He was the subject of several attacks by artists and critics due to his taste veering more to old art and academicism than contemporary art - he refused to acquire works by some already-acclaimed artists such as Camille Corot who he did not appreciate.