Hugues-Félicité Robert de Lamennais (or de la Mennais) (19 June 1782 - 27 February 1854), was a French Catholic priest, philosopher, and political theorist. He was one of the most influential intellectuals of Restoration France. Lamennais can be considered the forerunner of liberal Catholicism, and social Catholicism.
His famous opinions on matters of religion and government changed dramatically over the course of his life. He initially held rationalistic views, but in part due to the influence of his brother, Jean-Marie, came to see in religion an antidote for the anarchy and tyranny unleashed by revolution. He derided Napoleon, in part because of the Organic Articles which unilaterally amended the Concordat of 1801 with the papacy. Lamennais assailed the Gallican tradition and was a staunch ultramontane for a time.
Lamennais was born at Saint-Malo in the ancient Province of Brittany on June 19, 1782, the son of a wealthy merchant who had recently received a coat of arms from the king. He lost his mother at the age of five and as a result, he and his brother, Jean-Marie, were sent for education to an uncle, Robert des Saudrais at La Chênaie, an estate near Saint-Malo. Resistant to any kind of discipline, his uncle would lock him in the library where he spent long hours reading Rousseau and Pascal, among others, and acquired a vast and varied learning. Revolution was to have a profound effect on Lammennais. His family sheltered non-juring priests. Father Vielle said Mass on occasion in the dark at La Chênaie.
Of a sickly and sensitive nature, and shocked by the events of the French Revolution, Lamennais developed a morbid frame of mind. He first held rationalistic views, but partly through the influence of his brother Jean-Marie and partly as a result of his philosophical and historical studies, he came to see the power of faith and religion. He voiced his convictions in Réflexions sur l'état de l'église en France pendant le 18ieme siècle et sur sa situation actuelle, published anonymously in Paris in 1808. The idea for this work and the materials were due to Jean-Marie, but the actual writing was done almost exclusively by Félicité. It recommended religious revival and active clerical organization and the awakening of an ultramontane spirit. Napoleon's police deemed the book dangerously ideological and tried to suppress it.