Ancient Diocese of Tarentaise

The Archdiocese of Tarentaise (Latin: Tarantasiensis) was a Roman Catholic diocese and archdiocese in France, with its see in Moûtiers, in the Tarentaise Valley in Savoie. It was established as a diocese in the 5th century, elevated to archdiocese in 794, and disbanded in 1801. The diocese of Tarentaise was again formed in 1825, and united with the diocese of Chambéry and diocese of Saint-Jean-de-Maurienne to form the Archdiocese of Chambéry, Maurienne and Tarentaise in 1966.

Legend relates that the Centrones were evangelized in the fifth century by James the Assyrian, secretary to St. Honoratus, Archbishop of Arles. He became the first Bishop of Darantasia or Tarentaise, the metropolis of the Centrones, and named St. Marcellus as his successor.

The first document in which the Diocese of Tarentaise is reliably mentioned is a letter of Leo the Great (5 May, 450) which assigns to the Archdiocese of Vienne, among other suffragans, the Bishop of Tarentaise. The first historically known bishop is Sanctius, who in 517 assisted at the Council of Epaon. A plea was brought before the Council of Frankfort (794) against the decision of Leo I that had been confirmed by Popes Symmachus and Gregory the Great. Leo III partly acceded to this plea, and made Darantasia a metropolis with three suffragans, Aosta, Sitten (Sion in French), and Maurienne, but maintained the of Vienne. For four centuries this primacy was the cause of conflicts between the archbishops of Tarentaise and those of Vienne; subsequently Maurienne was again attached to the metropolis of Vienne.

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