Roman Catholic Diocese of Trier

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.

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