Armand Jean Le Bouthillier De Rance, reformer of the monastery of La Trappe, born in Paris, Jan. 9, 1626, died Oct. 27, 1700. He was a godson of Cardinal Richelieu, and at the age of 12 published an edition of Anacreon, with notes and comments. Though ordained a priest in 1651, he led a dissipated life, and was an assiduous visitor at the hôtel Rambouillet, where he fell in love with the duchess de Montbazon. After her death he submitted himself to severe penances, gave his property to the poor, and resigned all his benefices except the abbey of La Trappe, to which he retired in 1662. Impressed with the necessity of a reform in monastic life, he went to Rome in 1664 to obtain from the pope permission to enforce in France the rules of the former " strict observance of Cîteaux." He failed in his mission, but on his return in 1666 he introduced the most rigorous regulations into his own community. In 1683 he published a treatise De la sainteté et des devoirs de la vie monastique, and in 1690 assumed the spiritual direction of the convent of Les Clairets, a female community dependent on that of La Trappe, and composed his Réflexions sur les quatre évangélistes. In 1695, having brought on a severe disease by his austerities, he resigned his abbacy and remained a private monk in the convent, redoubling his penances, and finally breathing his last upon a bed of straw and ashes.

His life was written by his contemporaries Maupeau, Marsollier, and Lenain de Tillemont, by Chateaubriand (Paris, 1844), and by C. Butler (London, 1814).