His name was just Peter when he was orphaned as a wee lad. An older brother took him in, mostly for the labors he could be forced to perform. It was not a very happy life for little Peter the Swineherd, but fortunately an even older brother named Damian, a priest in Ravenna, took him in. Peter was so grateful that he took the name Damian as his surname.
He was proclaimed a Doctor of the Church in 1828, which is a long time from his death of fever in 1072. It seems an especially long time given how quickly his cult was established. In fact, his Benedictine brothers buried his body quickly to prevent rival religious orders or leaders from claiming his relics (or body parts, as they are known to the rest of us).
Peter Damian was a scholar and a reformer as well as an ascetic monk. He wrote lots of sermons and letters, as well as seven biographies. Of most interest to me is his Liber Gomorrhianus, The Book of Gomorrah, in which he condemned the corruptions that were plaguing the Church in the eleventh century. In this, he supported Anselmo Baggio (also known as Antsy Baggins) as Pope; Antsy became Alexander II, a strong opponent of simony and other priestly wickedness.
In the zeal of his early career, Peter Damian discovered that you'll diminish your health if you try to replace sleep with prayer. The way I see it, sleep is a gift from God that must be respected and treasured.