St Concordius is probably depicted in this fresco

from San Salvatore together with with St Senzius

St Concordius first appears under 1st January in the Martyrology of Adon (858).

An entry in the Roman Martyrology under 1st January reads:

1. “At Spoleto, in the time of Emperor Antoninus, St. Concordius, priest and martyr, who was beaten with clubs, then stretched on the rack, and after a long confinement in prison, where he was visited by an angel, lost his life by the sword.”
   

A copy of the legend of St Concordius (BHL 1906) is preserved in the Leggandari del Duomo.

According to the legend, St Concordius was martyred in the reign of the Emperor Antoninus Pius (138-61) and was thus one of the protomartyrs of Spoleto.  He was buried "non longe a civitate Spoletana, ubi multae emanant aquae” (not far from Spoleto, in a place where there was abundant water).   (For the historical background, see the page on Early Christianity in Spoleto).

His burial probably took place in the early Christian cemetery near what is now the church of San Salvatore, which was first documented in 1064 as the "monasterium sancti concordi".  It was subsequently known as SS Concordio e Senzia (see St Senzius).  The relics of these saints are preserved in an urn (1727) with an identifying inscription that could reproduce an older one.  [Where is the reliquary ??]