Peter Tyrrell (1916 – 26 April 1967) was an Irish author and former inmate of St Joseph's Industrial School, Letterfrack, an institution run by the Christian Brothers.
Tyrrell was born in 1916 to poor parents near Cappagh, Ahascragh, County Galway, Ireland. His mother begged to support her family, and when Peter was aged eight the authorities petitioned the courts to place him and three of his siblings into St Joseph's Industrial School, where he remained until he was 16.
He worked as a tailor in Ballinasloe for a while, then in 1935 he emigrated and in 1939 joined the British Army. While in the Army in India, he realised he was treating Indians badly and felt he was behaving like the Christian Brothers in Letterfrack. He was captured during World War II and held in a German prisoner-of-war camp where he felt treated better than in Letterfrack.