of Troyes was reduced to ashes by an invasion of Northmen. There have been several councils held at Troyes, including those of 867, 878 (over which Pope John VIII presided), 1078, 1104 and 1107 (over which Pope Paschal II presided). Cathedral, Collegiate Churches, Parishes The Cathedral of Troyes is a fine Gothic structure begun in the 12th century, and completed in the 15th. The Cathedral Chapter has eight dignities: the Dean (who is elected by the Canons), the Treasurer, the Cantor, the Great Archdeacon (the Archdeacon of Troyes), the Archdeacon of Sessana, the Archdeacon of Arceis (Arcis), the Archdeacon of Brienne, and the Archdeacon of S. Margarita (Margerie). There were thirty-seven Canons, one of whom was the Prior of S. Georges de Gannayo. The Canons were appointed alternately by the Bishop and by the King. The most famous of the Deans of Troyes was Petrus Comestor (ca. 1110–1179), who was born in Troyes and became a priest of the diocese; he was then professor of theology in Paris, and Chancellor of the Cathedral of Notre-Dame de Paris. In the diocese of Troyes there were ten collegiate churches: Saint-Étienne, in Troyes, a college royale Saint-Urbain, in Troyes (founded by Pope Urban IV ca. 1264) Saint Nicolas de Sézanne (founded 1164) Lirey (founded 1353) Broyes (founded 1081) Pleurs (founded 1180) Pougy (founded 1154) Plancy (founded 1206) Villemaur (founded 1124) Beaufort-Montmorency At the beginning of the fifteenth century there was a grand total of 185 Canons in the diocese of Troyes. By the beginning of the eighteenth, there were only 117. At the beginning of the fifteenth century there were 358 parishes in the diocese. The ancient collegiate Church of St. Urbain is a Gothic building whose lightness of treatment is reminiscent of La Sainte-Chapelle at Paris. Its construction was begun by Urban IV in 1262; the choir was completed in 1265, though the edifice was damaged by fire in 1266. The nave and façade are of the 19th and 20th centuries. Urban was a native of Troyes, and he prevailed upon the nuns of Notre-Dame-aux-Nonnans to sell him the land on which his father's house stood for a new church; on one of the stained-glass windows he caused his father to be depicted, working at his trade of tailor. The College of twelve Canons was headed by a Dean, and there was a Cantor and a Treasurer. On 20 June 1353, Geoffroy