St. Peter Damian (1007-1072) was an Italian eremitic monk and ecclesiastical reformer whose writings were among the most influential of the 11th century. Damian battled relentlessly against the ecclesiastical corruption of his day, speaking the truth fearlessly to popes, bishops, and clergy. His corpus of works include dozens of books, sermons, and letters, which focus on the monastic life, the doctrines of the faith, and the correction of abuses that were rife in the Catholic Church at the time. He was given title of Doctor of the Catholic Church by Pope Leo XII in 1823.
