The diocese dates back to the 4th century. Traditionally the city was first evangelized around 332 by St Sanctinus, Bishop of Meaux, who became the first bishop. Sanctinus erected the first Christian oratory dedicated to St. Peter and St. Paul.[1][2]: pp.22–23
The first bishop known to history is St. Polychronius (Pulchrone) who lived in the fifth century and was a relative and disciple of St. Lupus de Troyes.[3] "Other bishops worthy of mention are: St. Possessor (470–486); St. Firminus (486–502); St. Vitonus (Vanne) (502–529); St. Désiré (Desideratus) (529–554), St. Agericus (Airy) (554–591), friend of St. Gregory of Tours and of Fortunatus; St. Paul (630–648), formerly Abbot of the Benedictine Monastery of Tholey in the Diocese of Trier; and St. Madalvaeus (Mauve) (753–776)."[4]
From 1624 to 1636, a large bastioned citadel was constructed on the site of the Abbey of Saint Vanne. The Church of Saint-Vanne was destroyed in 1832 and its cloister, which had been converted into barracks, was burned in 1870.[3]
During World War I over 200 parishes fell under occupation by the German army and communication with the Bishop of Verdun practically cut off.[5] The administration of the parishes was confided to Thomas Louis Heylen, Bishop of Namur, who had been appointed vicar apostolic to French territory under German occupation.[6]
When the city came under bombardment the diocesan administration relocated to Bar-le-Duc and did not return until 1921. One hundred and fifty-three churches were destroyed and 166 damaged, including the Cathédrale Notre-Dame de Verdun, whose towers have never been rebuilt. Of 186 priests who enlisted, 13 were killed, 20 seriously wounded, and 50 taken prisoner. One hundred and sixty citations and diplomas of honor and 120 decorations were awarded to priests of the diocese.[5]
1548–1575: Nicolas Psaume. The Bishopric was annexed to France in 1552. This was not formally recognised in the Empire until the Peace of Westphalia in 1648.
Until 1801 Verdun was part of the ecclesiastical province of the Archbishop of Trier. On November 29, 1801 it was suppressed and added to the Diocese of Nancy. On October 6, 1822 the diocese was re-established.
^François-Alexandre Aubert de La Chesnaye Des Bois. "Dictionnaire de la noblesse : contenant les généalogies, l'histoire et la chronologie des familles nobles de France", (Paris: Schlesinger Brothers, 1867), p. 993.