AGEN, DIOCESE OF. - A city in southern France in Languedoc, situated on the Garonne River at its confluence with the Masse; it is the ancient Aginnum, and today has 27,500 inhabitants. It was once the chief town of the Civitas Agennensium and then the capital of the kingdom of the Nitiobroges, which disappeared with the Roman conquest. It is not known precisely when Christianity was introduced there. Around the middle of the 4th century, the Church of A. is illustrated by St. Phoebadius (v.). He was already bishop of A. when he wrote his Liber contra Arianos in 357, and after being one of the principal actors at the Council of Rimini in 359, he presided over those of Valence in 374 and of Saragossa in 380. A. boasts among its priests the man who was called the Christian Sallust, Sulpicius Severus (v.). Occupied by the Visigoths from 412 to 507, and devastated by the Saracens and finally by the Normans in the year 848, A. rose again from its ruins in 912 and enjoyed a flourishing of monastic institutions, despite the conflicts of heresy. It was under the rule of the kings of England, particularly from 1360 to 1463, and annexed to the Crown of France in 1615. It is renowned for its beautiful church of St. Caprasius, in the Gothic style of the 12th-13th centuries.
The diocese, which following the Concordat of 1801 had absorbed the suppressed diocese of Auch and part of that of Montauban, has as its territory the department of Lot-et-Garonne (538 sq. km., and 247,500 inhabitants) and counts 200,000 Catholics, divided into 440 parishes administered by 263 priests. It currently depends on the metropolitan see of Bordeaux after having been united to that of Toulouse from 1802 to 1823.