The Roman Catholic diocese of Trier, in English traditionally known by its French name of Treves, is a diocese of the Latin Rite of the Roman Catholic church in Germany. When it was the archbishopric and Electorate of Trier, it was one of the most important states of the Holy Roman Empire, both as an ecclesiastical principality and as a diocese of the church. Unlike the other Rhenish dioceses — Mainz and Cologne, Trier was the former Roman provincial capital of Augusta Treverorum. Given its status, Trier has always been the seat of a bishop since Roman times, one of the oldest dioceses in all of Germany. The diocese was elevated to an Archdiocese in the time of Charlemagne and was the metropolitan for the dioceses of Metz, Toul, and Verdun. After the victory of Napoleon Bonaparte of France, the archdiocese was lowered to a diocese and is now a suffragan of the Archdiocese of Cologne. The diocesan cathedral is the Cathedral of Saint Peter.
The bishops of Trier were already virtually independent territorial magnates in Merovingian times. In 772 Charlemagne granted Bishop Wiomad complete immunity from the jurisdiction of the ruling count for all the churches and monasteries, as well as villages and castles that belonged to the Church of St. Peter at Trier. In his will he also elevated the diocese to the Archdiocese of Trier, with suffragans on both sides of the Rhine. This arrangement lasted over a thousand years.
In Early Modern times, the archdiocese of Trier still encompassed territory along the Moselle River between Trier, near the French border, and Koblenz on the Rhine. The Archbishop of Trier, as holder of an imperial office was traditionally an Imperial Elector of the German king. The purely honorary office of Archchancellor of Gaul arose in the 13th century. In this context that was taken to mean the Kingdom of Arles, or Burgundy, technically from 1242 and permanently from 1263, and nominally until 1803. Arles along with Germany and Italy was one of the three component kingdoms of the Empire.
The last elector removed to Koblenz in 1786. From 1795, the territories of the Archbishopric on the left bank of the Rhine — which is to say almost all of them — were under French occupation, and were annexed in 1801 and a separate bishopric established (later assuming control of the whole diocese in 1803). In 1803, what was left of the Archbishopric was secularized and annexed by the Princes of Nassau.
Auspicius of Trier c. 130, uncertainEucharius c. 250Valerius c. 250Maternus c. 300Agricius (Agrippinus) 327-335Maximinus II 335–352Paulinus 353–358Bonosus of Trier 359–365Veteranius of Trier 365–384Britto of TrierFelix II 384–398Mauritius II of Trier 398–407Leontius of Trier 407–409Auctor II 409–427Severus of Trier 428–455Cyrillus of Trier 455–457Iamblichus of Trier 457–458Evemerus 458–461Marcus II 461–465Volusianus of Trier 465–469Miletius 469–476Modestus 476–479Maximianus of Trier 479–499Fibicius 500–526Aprunculus (Aprunentius) 526–527Nicetius 527–566Rusticus II 566–573Magnerich 573–596Gunderich 596–600Sibald 600–626Modoald 626–645Numerianus 645–665Hildulf 665–671, d. 707Basinus 671–697 d. 706 ?Leudwinus 697–718Milo 718–758Wermad 758–791Richbod 791–804, first archbishopWaso 804–809Amalhar 809–814Hetto 814–847Dietgold 847–868Bartholf von Wetterau 869–883Radbod 883–915Rudgar 915–930Rotbert 930–956Henry I 956–964Dietrich I 965–977Egbert 977–993Ludolf 994–1008Megingod 1008–1015Poppo von Babenberg 1016–1047Eberhard 1047–1066Kuno I von Wetterau (Conrad) 1066–1066Udo of Nellenburg 1066–1078Egilbert of Rothenburg, 1079–1101Bruno 1101–1124Gottfrid 1124–1127Meginher 1127–1130Albero de Montreuil 1131–1152Hillin of Falmagne 1152–1169Arnold I of Vaucourt 1169–1183Folmar of Karden 1183–1189 Rudolf of Wied 1183-1189 (in opposition)John I 1189–1212Theodoric II 1212–42Arnold II von Isenburg 1242–59Heinrich I von Finstingen 1260–86Bohemond I von Warnesberg 1286–99Diether von Nassau 1300–07Heinrich II von Virneburg 1300–06 (in opposition)Baldwin von Luxemburg 1307–54Bohemond II von Saarbrücken 1354–61Kuno II von Falkenstein 1362–88Werner von Falkenstein 1388–1418Otto von Ziegenhain 1418–30Rhaban von Helmstadt 1430–38Jakob von Sierck † (19 May 1439 Appointed - 28 May 1456 Died)Johann Markgraf von Baden † (21 Jun 1456 Appointed - 9 Feb 1502 Died)Jakob Markgraf von Baden † (9 Feb 1503 Succeeded - 27 Apr 1511 Died)Richard von Greiffenclau zu Vollrads † (15 May 1511 Appointed - 13 Mar 1531 Died)Johann von Metzenhausen † (27 Mar 1531 Appointed - 22 Jul 1540 Died)Johann Ludwig von Hagen † (9 Aug 1540 Appointed - 23 Mar 1547 Died)Johann von Isenburg † (20 Apr 1547 Appointed - 18 Feb 1556 Died)Johann von der Leyen † (25 Apr 1556 Appointed - 10 Feb 1567 Died)Jakob von Eltz † (7 Apr 1567 Appointed - 4 Jun 1581 Died)Johann von Schönenberg † (31 Jul 1581 Appointed - 1 May 1599 Died)Lothar von Metternich † (7 Aug 1599 Appointed - 17 Sep 1623 Died)Philipp Christoph Reichsritter von Sötern † (25 Sep 1623 Appointed - 7 Feb 1652 Died)Karl Kaspar Reichsfreiherr von Leyen-Hohengeroldseck † (7 Feb 1652 Succeeded - 1 Jun 1676 Died)Johann Hugo von Orsbeck † (1 Jun 1676 Succeeded - 6 Jan 1711 Died)Karl Joseph Ignaz Herzog von Lothringen † (24 Sep 1710 Appointed - 4 Dec 1715 Died)Franz Ludwig Pfalzgraf am Rhein zu Neuburg † (20 Feb 1716 Appointed - 3 Mar 1729 Resigned)Franz Georg Reichsfgraf von Schönborn † (2 May 1729 Appointed - 18 Jan 1756 Died)Johann Philipp Reichsgraf von Waldendorff † (18 Jan 1756 Succeeded - 12 Jan 1768 Died)Klemens Wenzeslaus Herzog von Sachsen † (10 Feb 1768 Appointed - 29 Nov 1801 Resigned)Charles Mannay † (5 Jul 1802 Appointed - 9 Oct 1816 Resigned)Josef von Hommer † (3 May 1824 Appointed - 11 Nov 1836 Died)Wilhelm Arnoldi † (21 Jun 1842 Appointed - 7 Jan 1864 Died)Leopold Pelldram † (29 Dec 1864 Appointed - 3 May 1867 Died)Matthias Eberhard † (16 Jul 1867 Appointed - 30 May 1876 Died)Michael Felix Korum † (12 Aug 1881 Appointed - 4 Dec 1921 Died)Franz Rudolf Bornewasser † (27 Feb 1922 Appointed - 20 Dec 1951 Died)Matthias Wehr † (20 Dec 1951 Succeeded - 19 Nov 1966 Retired)Bernhard Stein † (13 Apr 1967 Appointed - 5 Sep 1980 Retired)Hermann Josef Spital † (24 Feb 1981 Appointed - 15 Jan 2001 Retired)Reinhard Marx (20 Dec 2001 Appointed - 30 Nov 2007 Translated to become Archbishop of Munich and Freising)Stephan Ackermann (8 Apr 2009 Appointed - )Nicolas Arlon, O. Carm. (1344–)Gerhard, O.F.M. (1429–1456)Johann von Eindhoven, C.R.S.A. (1483–1508)Johannes von Helmont, O.S.B. (1508–1517)Johannes Enen (1517–1519)Nikolaus Schienen (1519–1556)Peter Binsfeld (1580–1598)Gregor Helfenstein (1599–1632)Otto von Senheim, (Johann Theodor von Senheim) O.P. (1633–1662)Johannes Holler (1663–1671)Johann Heinrich von Anethan (1676–1680)Maximilian Burmann (1682–1685)Johann Matthias von Eyss (1710–1729)Lothar Friedrich von Nalbach (1730–1748)Johann Nikolaus (Febronius) von Hontheim (1748–1790)Jean-Marie Cuchot d’Herbain (1778–1794)Johann Michael Josef von Pidoll de Quitenbach (1794–1802)Johann Heinrich Milz (1825–1833)Wilhelm Arnold Günther, O. Praem. (1834–1843)Johann Georg Müller (1844–1847)Godehard Braun (1849–1861)Matthias Eberhard (1862–1867 Appointed, Bishop of Trier)Johann Jakob Kraft (1868–1884)Heinrich Feiten (1887–1892)Anton Mönch (1915–1935)Albert Maria Fuchs (1935–1944)Heinrich Metzroth (1941–1951)Carl Schmidt (1962–1981)Karl Ernst Schrod (1894–1914)Bernhard Stein (1944–1967 Appointed, Bishop of Trier)Johannes Petrus Verhorst (1687–1708)Joannes Franqueloy de Vico, O.P. (1400–1452)Gregor Virneburg (1557–1578)Hubert Yffz (de Rommersdorf), O. Praem. (1450–1483)Karl Heinz Jacoby (1968–1993)Alfred Kleinermeilert (1968–2003)Leo Schwarz (1982–2006)Gehard Jakob (1993–1998)Felix Genn (1999–2003, Translated to become Bishop of Essen and later Bishop of Münster)Robert Brahm (2003-)Jörg Michael Peters (2003–)Stephan Ackermann (2006–2009 Appointed, Bishop of Trier)Helmut Dieser (2011–2016, Translated to become Bishop of Aachen)
