BARBIER DE MONTAULT, XAVIER-MARIE-JOSEPH. — French scholar, born at Loudun on 6 February 1830, died at Blaslay on 29 March 1901. At the age of 23 he went to Rome, where he spent a long time, traveling almost throughout Italy, France, and Germany, visiting museums, studying monuments, and researching archives.
His published writings number more than 4,
000. Many of these, collected in 16 volumes, were published in Poitiers between 1889 and 1902 under the title *Oeuvres complètes de Mgr X
M.-J. B. de M. Prélat de la Maison de Sa Sainteté*. They include inventories of churches in Rome, the Vatican Palace, and the pontifical museums; as well as topics such as papal law, popular devotions, hagiography, ceremonies concerning the conclave, and pontifical etiquette.Among his works of an archaeological nature, besides *Tableau raisonné des pierres et marbres antiques employés à la construction des monuments de Rome* (n.d.) and the volume *Les Musées et Galeries de Rome – Catalogue général de tous les objets d'art qui y sont exposés* (1870), notable are *Les églises de Rome étudiées au point de vue archéologique*, *Description de la Basilique de S. Paul hors-les-murs à Rome* (1866), *Les souterrains et les trésors de S. Pierre à Rome ou description des objets d'art et d'archéologie qu'ils renferment* (1866), and *Antiquités chrétiennes photographiées par M. Ch. Simelli cataloguées et décrites* (1870). In the first volume of the *Revue de l'art chrétien* (1857), some articles appeared on the *Épigraphie des Catacombes*. Also worthy of note are the *Traité pratique de la construction, de l'ameublement et de la décoration des églises*, published in Paris in two volumes in 1872, and the *Traité d'iconographie chrétienne*, likewise published in Paris in two volumes in 1890. Finally, mention should be made of the study *Le Martyrium de Poitiers. Comprendu des fouilles et de l'ouvrage du r. p. De La Croix* (1855) and the extensive memoir in the *Revue d'art chrétien*, 40 (1896), on *Les mosaïques des églises de Ravenne* (5th–7th centuries), in which he highlighted their historical, archaeological, and artistic importance.