Born at Volterra in the province of Pisa, little is known about his life. He was head of the church following the death of Peter and during his pontificate five emperors held power, Nero, Calba, Otho, Vitellius and Vespasian. During his period of office ocurred the martyrdoms of the evangelists Mark and Luke. He is credited with the decree which forced women to attend religious functions and holy sites with heads covered. During this period of office were born gnostic heresies.
Martyred under Vespasian he was buried next to Saint peter.