Peter was born in Ravenna in the year 1007. His tutor was his brother Damian, which likely explains the surname Damiani. After studying in Ravenna, Faenza, and Padua, he withdrew to the solitude of Fonte Avellana. However, he had to leave for a time to take on a preaching role offered to him by Pomposa and other monasteries. Later, he returned to Fonte Avellana, where he was appointed prior.
He founded and reformed monasteries, bringing them together into a congregation strongly inspired by the Camaldolese tradition. Emperor Henry III and several popes called him out of his solitude to fight against two major issues of the time: simony and the immorality of the clergy. He worked alongside another great reformer, Hildebrand (the future Pope Gregory VII), though they disagreed on some methods.
Peter was appointed cardinal and bishop of Ostia, one of the suburbicarian dioceses. However, after becoming disillusioned with his efforts to reconcile the papacy and the empire, he resigned from his episcopal duties and returned to monastic life. Even then, he was sent on several political and ecclesiastical missions across France, Germany, and many parts of Italy.
He died in 1072 and was immediately venerated as a saint, though his cult did not become universal until Pope Leo XII officially declared him a Doctor of the Church in 1828—an honor well deserved for his extensive literary work. Dante placed him in the seventh heaven among the contemplatives in The Divine Comedy.
Peter Damian passed away at the Monastery of Santa Maria fuori Porte in Faenza on the night of February 22. His feast was traditionally celebrated on February 23, since February 22 was reserved for the Feast of the Chair of Saint Peter. In the current liturgical calendar, February 23 is now dedicated to Saint Polycarp, so Saint Peter Damian’s memorial has been moved to February 21.