A theologian and diplomat, born 25 Nov., 1556, at St-Lô (Normandy), France; died 5 Sept., 1618, at Batignolles, a suburb of Paris. His parents were Calvinists and on account of persecution sought refuge in Switzerland soon after his birth. Having received a thorough literary, scientific, and philosophical education, he applied himself to the study of the Fathers and ecclesiastical writers, especially St. Augustine and St. Thomas Aquinas, and in 1577 or 1578 was converted to the Catholic Faith. He enjoyed the favour and confidence of King Henry III, to whom he had been presented in 1576, and later that of Henry IV. The latter's conversion was to a great extent due to Duperron's instructions and influence, and his absolution from heresy was obtained from the pope by Duperron and Cardinal d'Ossat (1595). While in Rome for that purpose, Duperron was consecrated Bishop of Evreux, a see to which King Henry IV had already appointed him in 1591, though he was not yet in Holy orders. Immediately after his conversion Duperron began to work with untiring zeal for the conversion of Protestants. By his science, eloquence, and power of argument he won many victories in controversies and conferences with ministers of the reformed sects. In 1600 the famous Fontainebleau conference took place with the leader of French Calvinism, Duplessis-Mornay, who had been accused by Duperron of mutilating, falsifying, and misinterpreting texts from the Fathers in his work on the Eucharist. Of the judges three were Catholics, and three Calvinists. On 4 May nine passages were examined concerning which the commission decided against Duplessis. The latter's real or feigned sickness and his departure prevented further meetings.

Duperron was created a cardinal in 1604. The same year he went to Rome, and was invited to assist at the meetings of the Congregatio de Auxiliis which Clement VIII had summoned to end the discussions on grace and freedom. Meanwhile he took an important part in the election of Leo XI and Paul V. The decision of Paul V not to condemn the Molinistic system was due largely to Duperron's advice. Duperron became Archbishop of Sens in 1606. In 1611 he stopped the decision of the Parliament condemning one of Bellarmine's works, and defended the latter's thesis of the pope's infallibility and superiority over councils. At a synod held at Paris (1612) he condemned the work "De ecclesiastica et politicâ potestate" by Edmond Richer, syndic of the Sorbonne. In 1614-15, at the meeting of the States General at Paris, he urged, against the Third Estate, the acceptance of the decrees of the Council of Trent on discipline and reform. Duperron's knowledge and eloquence were so great that Pope Paul V said of him: "Let us pray that God may inspire Duperron, for he will persuade us of whatever he pleases."

His works were collected in three volumes (Paris, 1620 and 1622). The first volume contains his "Traité du sacrement de l'Eucharistie " written against Duplessis-Mornay. Its three books deal with;

(1) a comparison of the Eucharist and the other sacraments of the New Law with those of the Old Law;

(2) the tradition of the Fathers, to which is added a special study of St. Augustine's doctrine;

(3) the practice of the Church concerning the adoration of the Eucharist.

The second volume is the "Réplique à la Réponse du Roy de la Grande-Bretagne". James I of England claimed that he belonged to the Catholic Church, as he believed all truths considered necessary by the first Christians. In his answer Duperron treats of the characteristics of the Catholic Church, of some articles which the king did not look upon as essential, the preservation and integrity of the doctrine and discipline of the Church, the Eucharist as a sacrament and a sacrifice, the invocation of the Saints, the use of Latin, translation of Holy Scripture, etc. The third volume contains various works among which are a treatise on vocation, the Acts of the Fontainebleau conference, a refutation of the work of Tilenus on Apostolic traditions, some moral and spiritual treatises, and poems both Christian and profane. Duperron's secretary, César de Ligny, wrote "Ambassades et négociations du cardinal Duperron" (Paris, 1618). Under the title of "Perroniana", remarks on theological, political, and literary subjects were published by Christophe du Puy from the notes of his brother, who had been with Duperron for a long time.

FÉRET, Le cardinal Duperron (Paris, 1877); DE BURIGNY, Vie du cardinal Duperron (Paris, 1768); DUPIN, Nouvelle bibliothèque des auteurs ecclésiastiques (Paris, 1710), XVII, 25; RÄSS, Die Convertiten seit der Reformation (Freiburg, 1866), II, 226, 441, III, 384; Gallia christiana (2d ed., Paris, 1870), XI, 612, XII, 96; SEIDL in Kirchenlexicon, IV, 26.

C. A. DUBRAY.