CALAHORRA e LA CALZADA, DIOCESI di. — C. is a city in northern Spain, in the old kingdom of Castile, in the province of Logroño, and the seat of a diocese
suffragan to Burgos. Bordered by the dioceses of Vitoria to the north, Pamplona to the northeast and east, Tarazona to the east, Osma to the south, and Burgos to the west, its territory extends over almost the whole province of Logroño, including the capital, and over parts of the provinces of Navarra (21 parishes), Soria (51 parishes), and Burgos (48 parishes), covering an area of 5,114 sq. km. It has a population of approximately 235,000 inhabitants. It possesses 737 churches and 353 parishes, served by 454 priests and 124 religious (1948). Its patrons are St. Emeterio, St. Celedonio, and St. Domenico de La Calzada.
It has two cathedrals (Calahorra and La Calzada) and a collegiate church (Logroño). C., the Roman Calagurría, situated along the great military road linking Tarragona with Galicia, was one of the Spanish cities where Christianity arrived early. The martyrdom of SS. Emeterio and Celedonio under Diocletian, later celebrated by Prudencio in his Peristephanon (VIII), proves that a Christian community existed in C. at the beginning of the 4th century. We do not know when the ecclesiastical hierarchy was established there, but certainly it was between the 4th and 5th centuries. Tarragona already had its metropolitan in 384, upon whom C. depended, and in 457 it certainly had its own bishop, named Silvano, against whom Ascanio of Tarragona protested to Pope Ilaro for having irregularly ordained men as bishops. Following the Muslim invasion of the 8th century, the hierarchy of the diocese was dispersed, but in the following century its territory still remained outside Muslim rule and was divided between two recently founded dioceses: Nájera (Rioja) and Alava, in Basque territory, whose see was at Armentia. After C. was conquered by Navarrese forces (1044), however, Nájera was absorbed by the ancient see in 1045, after barely a century or somewhat more of existence, and the same happened shortly afterward to Alava (1088). In the 13th century the episcopal see of C. was transferred to La Calzada, which gave rise to serious disputes, settled shortly afterward, in 1256, when the bishop returned to C. but also assumed the title of La Calzada. Following the provisions of the Concordat of 1851, the Basque part of its territory passed to the new diocese of Vitoria, erected by Pius IX in 1862. Initially suffragan to Tarragona, in 1318 it became part of the province of Saragossa and finally, in 1574, of that of Burgos.
The cathedral of C., dedicated to the Assumption, has three naves in the pointed-arch style and is of questionable architectural merit; it underwent extensive reconstruction in the 15th century. That of La Calzada, in the Romanesque style, was begun in 1168. The collegiate church of Logroño is noteworthy: it has three naves, is in the pointed-arch style, dates from the 15th century, and has a Latin-cross plan distinguished by its eight pillars. Its main entrance does not harmonize with the architectural style of the church; it was in fact built in the 18th century, while the spherical niche serving as the entrance to its two slender towers produces a pleasing effect. The side doors are Renaissance; the chapels of the apse date from the 17th century; the choir from the end of the 16th; and the high altar from the end of the 17th.