DUCHESNE, LOUIS MARIE OLIVIER French scholar and ecclesiastic, was born at St. Servan, Brittany, on Sept. 13, 1843. He was educated at the seminary of St. Brieuc and at Rome and was ordained priest in 1867. In he went on a scientific expedition to Mt. Athos and in 1876 to Asia Minor ; but his interest in the history of the Western Church appeared in 1877 when he received the degree of docteur es lettres with two remarkable theses, a dissertation De Macario magnete, and an Etude sur le Liber pontificalis, an acute critical study of the origin and editions of that celebrated chronicle. Immediately afterwards he was appointed professor at the Catho lic Institute in Paris, and for eight years presented the example, then rare in France, of a priest teaching church history accord ing to the rules of scientific criticism. His course, bold even to the point of rashness in the eyes of the traditionalists, was at length suspended. In Nov. 1885 he was appointed lecturer at the Ecole Pratique des Hautes Etudes. In 1886 he published vol. i. of his learned edition of the Liber pontificalis (completed in 1892 by vol. ii.). In 1888 he was elected member of the Academie des Inscriptions et Belles-Lettres, and was afterwards appointed director of the French school of archaeology at Rome. Much light is thrown upon the Christian origins, especially those of France, by his Origines du culte chretien, etude sur la liturgie latine avant Charlemagne (1889; Eng. trans. by M. L. McClure, Christian Worship: its Origin and Evolution, London, 5th ed. 1919) ; Memoire sur l'origine des dioceses episcopaux dans l'ancienne Gaule (189o), the preliminary sketch of a more de tailed work, Fastes episcopaux dans l'ancienne Gaule and Catalogues episcopaux de la province de Tours (1898). His Autonomies ecclesiastiques; eglises separees (1897 ; Eng. trans. by H. H. Mathew, 1907), in which he speaks of the origin of the Anglican Church, but treats especially of the origin of the Greek Churches of the East, was received with scant favour in certain narrow circles of the pontifical court. In the Histoire ancienne de l'eglise, 4th ed. (1908; Eng. trans. by C. Jenkins, Duchesne touches cleverly upon the most delicate problems, and, without any elaborate display of erudition, presents notable con clusions. L'Eglise an VIe siecle was published posthumously in 1925. His incisive style, his fearless and often ruthless criticism, and his wide and penetrating erudition, make him a redoubtable adversary in the field of polemic. The Bulletin critique, a review of history, philology and theology, founded by him in 188o, has contributed powerfully to spread the principles of the historical method among the French clergy.
Duchesne received an honorary Litt.D. from Cambridge and D.Litt. from Oxford, and in 1910 was elected to the French Academy. He died on April 21, 1922.
See C. D. 'Habloville, Grandes Figures de l'Eglise contemporaine Mgr. Duchesne (1925).