Name change
He lived during the reign of Emperor Antoninus Pius, who chose the title "Pius", latin for "dutiful", out of respect to his predecessor, Hadrian. It is believed that this Bishop of Rome also chose, or was ordained as, "Pius" out of respect and loyalty to the present Emperor.Heresies
Gnosticism was still growing within the Roman church during his time, while the church had already been excommunicating some of the more radical members. Pope Pius I presided over a council that excommuncated the Gnostic Marcion, who would go on to found the Marcionite cult.Easter
He is believed to have officially mandated the observation of the Last Supper on Easter. He is also claimed to have decreed various forms of punishments of penance to priests who drop or spill the bread or wine.Death
No documents have been found to prove claims that he was martyred, or beliefs that he may have been assassinated.138-161: Roman Emperor, Antoninus Pius