The Diocese of Langres (Latin: Dioecesis Lingonensis; French: Diocèse de Langres) is a Latin Church diocese of the Catholic Church comprising the département of Haute-Marne in France.
The diocese is now a suffragan in ecclesiastical province of the Archdiocese of Reims, having been a suffragan of Lyon until 2002. The current bishop is Joseph Marie Edouard de Metz-Noblat, who succeeded Bishop Philippe Jean Marie Joseph Gueneley on 21 January 2014. The diocese covers a territory of 6,250 km2 and its estimated catholic population is 128,000.
In 2021, in the Diocese of Langres there was one priest for every 2,782 Catholics.
Louis Duchesne considers Senator, Justus and Didier de Langres, who was martyred during the invasion of the Vandals (about 407), the first three bishops of Langres. The See, therefore, must have been founded about the middle of the fourth century.
In 1179, Hugh III, Duke of Burgundy gave the city of Langres to his uncle, Gautier of Burgundy, then bishop, making him a prince-bishop. Later, Langres was made a duchy, which gave the Duke-Bishop of Langres the right of secular precedence over his Metropolitan, the Archbishop of Lyon, at the consecration of the kings of France.
The chief patron saint of the diocese is the martyr Mammes of Caesarea (third century), to whom the cathedral, a monument of the late twelfth century, is dedicated. The diocese of Langres honors as saints some martyrs who, according to legend, died in the persecution of Roman Emperor Marcus Aurelius. They are the triplets Speusippus, Eleusippus, and Melapsippus; Neo, the author of their Acts; Leonilla, their grandmother; and Junilla, their mother. Other saints honored there include:
Valerius (Valier), a disciple of Desiderius, who was martyred by the Vandals in the fifth century
the hermit Godo (or Gou), nephew of Vandrillus in the seventh century
Gengulphus, martyr in the eighth century
Gerard Voinchet (1640–95), canon regular of the Congregation of St. Geneviève in Paris
Mariet, a priest who died in 1704
Joseph Urban Hanipaux, a Jesuit.
The latter three were natives of the diocese and celebrated for their apostolic labors in Canada.
The diocese was also the birthplace of the theologian Nicolas de Clémenges (fourteenth or fifteenth century), who was canon and treasurer of the Church of Langres; of the Gallican canonist Edmond Richer (1560–1631); of the Jesuit Pierre Lemoine, author of an epic poem on St. Louis and of the work La dévotion aisée (1602–71); and of the philosopher Diderot (1713–84). The historian Raoul Glaber, monk of Cluny Abbey who died in 1050, was at the priory of St. Léger in this diocese when he experienced an apparition.
The Benedictine Poulangy Abbey was founded in the eleventh century. Morimond Abbey, the fourth foundation of Cîteaux, was established in 1125 by Odolric, lord of Aigremont, and Simon, Count of Bassigny. The Augustinian priory of the Val des Écoliers was founded in 1212 at Luzy, near Chaumont, by four doctors of the Paris University who were led into solitude by a love of retreat.
Otho, son of Leopold of Austria and Abbot of Morimond, became Bishop of Freising in Bavaria and returned in 1154 to die a simple monk in Morimond.
The "Scourging of the Alleluia," now no longer observed, was quite celebrated in this diocese in the Middle Ages. On the day when, according to tradition, the Alleluia was omitted from the liturgy, a top on which the word "Alleluia" was written was whipped out of the church, to the singing of psalms by the choirboys, who wished it bon voyage till Easter.
The "Pardon of Chaumont" is very celebrated. In 1475, Jean de Montmirail, a native of Chaumont and a particular friend of Pope Sixtus IV, obtained from him that each time the feast of St. John the Baptist fell on a Sunday, the faithful, who confessed their sins and visited the church of Chaumont, should enjoy the jubilee indulgence. Such was the origin of the great "Pardon" of Chaumont, celebrated sixty-one times between 1476 and 1905. At the end of the Middle Ages, this "Pardon" gave rise to certain festivities. Fifteen mysteries of the life of St. John the Baptist were represented on stages erected throughout the town on the Sunday preceding the "Pardon." The display drew multitudes to the festivities, which were finally called the "deviltries" of Chaumont. In the eighteenth century, the "Pardon" became a purely religious ceremony.