St. Pope John I was the bishop of Rome from 13 August 523 to his death. He was a native of Siena (or the “Castello di Serena”, near Chiusdino), in Italy. He was sent on a diplomatic mission to Constantinople by the Ostrogoth King Theoderic to negotiate better treatment for Arians. Although relatively successful, upon his return to Ravenna, Theoderic had the Pope imprisoned for allegedly conspiring with Constantinople. The frail pope died of neglect and ill-treatment.

St. Pope John I is depicted in art as looking through the bars of a prison or imprisoned with a deacon and a sub deacon. He is venerated at Ravenna and in Tuscany. His feast day is 18 May, the anniversary of the day of his death.