John was very frail when he was
elected to the
papacy. Despite his protests, Pope John was sent by
Theodoric the Great, the
Arian king of the
Ostrogoths in Italy, to
Constantinople to secure the moderation of a decree, issued in 523, of
Justin I, emperor of the
Eastern Roman Empire, against the Arians. King Theoderic threatened that if John should fail in his mission, there would be reprisals against the non-Arian Christians in the West. John proceeded to Constantinople with a considerable entourage: including his fellow bishops
Ecclesius of Ravenna, Eusebius of
Fanum Fortunae, and Sabinus of
Campania. His secular companions were the
Roman senators
Flavius Theodorus,
Inportunus, and the Patrician
Agapitus. Emperor Justin is recorded as receiving John honorably and promised to do everything the embassy asked of him, with the exception that those converting from Arianism to Orthodoxy would not be "restored" (i.e., allowed to retain their place in the Orthodox hierarchy as deacons, priests, or bishops). Although John was successful in his mission, when he returned to
Ravenna, Theoderic's capital in Italy, Theoderic had John arrested on the suspicion of having conspired with Emperor Justin. John was imprisoned at Ravenna, where he died of neglect and ill treatment. His body was transported to
Rome and buried in the
Basilica of St. Peter. The
Liber Pontificalis credits John with making repairs to the cemetery of the martyrs
Nereus and Achilleus on the
Via Ardeatina, that of
Felix and Adauctus, and the cemetery of
Priscilla. ==Veneration==