Pope St. John I

Pope St. John I (born in Tuscany; reigned 523–526) was elected to the See of Peter during the reign of the Ostrogothic king Theodoric, an adherent of Arianism who ruled Italy. When the Eastern emperor Justin I issued measures against the Arians, Theodoric compelled the elderly pope to lead an embassy to Constantinople to seek their moderation — the first time a reigning pope traveled to the imperial capital.

The pope was received there with great honor and is said to have crowned the emperor and celebrated Easter in the great church. But Theodoric, suspicious that John had conspired with the Eastern court against him, arrested the pope on his return and imprisoned him at Ravenna, where he died of hardship and neglect in 526. The Church venerated him as a martyr for the faith, and his memory endured as that of a shepherd who suffered for the Church's independence from an Arian ruler.