Exactly when St. Sebastian was canonized is not known. The Church merely states that he was elevated to sainthood in "Pre-Congregation" times, as were many early saints--e.g., Saint Apphia, Saint Maris of Persia, Saint Nereus of Terracina among many others..

The earliest known representation of the martyr St. Sebastian is seen in a mosaic of between 527 and 585 C.E. in Sant' Apollinare Nuovo in Ravenna (See: Figure 1). In this mosaic the martyr-saint, one of a line, is represented as a Byzantine nobleman, tonsured and holding the wreath of martyrdom, no other iconic device is indicated. If it were not for his name floating over his head, he would be indistinguishable from the rest in that august assemblage. Also there is an early representation of St. Sebastian in San Pietro in Vincoli, Rome of 682 C.E. (See: Figure 2). Here, again, he is recognized by his name bracketing his body.