JACA, DIOSCESIS OF. — An Aragonese diocese situated in the civil provinces of Saragossa and Huesca and contiguous with the French dioceses of Bayonne and Tarbes-Lourdes. It is a suffragan of Saragossa. Scant information is available about this church in the early Middle Ages.
The cathedral was erected in the 11th century by King Ramiro I of Aragon, but ordinarily the diocese was united with that of Huesca until 1572, when, at the request of King Philip II, it was separated from Huesca and constituted as an independent see by Pope St Pius V. It was the first cathedral to adopt the Roman rite in place of the Visigothic; a council was celebrated there in 1063. The style of the building is Romanesque, sober yet elegant; in the 15th century its vaults were rebuilt, as was the cloister, which unfortunately has lost its original appearance. The plan of the cathedral consists of three naves, in addition to the transept, and three semicircular apses. The choir, which, as in other Spanish cathedrals, originally stood in the center of the church, was moved to the main altar in 1919. The church was dedicated in 1062, and its liturgical memory is renewed on 12 December; its patron is St Peter the Apostle, but the patroness of the diocese is St Ursula, whose body is venerated in the said cathedral. In 1785 the vicariate of Valdona, consisting of 48 villages previously belonging to Pamplona, was aggregated to this diocese; thus today the territorial extent of Jaca is 5,391 sq. km., with a population of 78,258 inhabitants, almost all Catholic, served by 154 parishes, 200 diocesan priests and 28 regulars, with 4 male and 18 female religious communities.
The seminary, founded in 1851 and destroyed by fire, has recently been rebuilt, as have many churches destroyed during the civil war of