In 1829 he published "De l'origine, de la nature, et des progrés de la puissance écclesiastique en France" the origin, nature, and progress of ecclesiastical power in France. In this book, Montlosier claims there were 500,000 affiliated Jesuits in France in the Chamber of Paris, in the Chamber of Deputies, at the court, in the army, in the courts, etc. He had no part in the revolution of 1830, but supported Louis Philippe's government, and entered the House of Peers in 1832. He died on December 9, 1838 at Blois. Ecclesiastical burial was denied him because he had refused to abjure his anti-clerical writings.