Saint Patrick is the patron saint of Ireland and is traditionally credited with bringing Christianity there.
Patrick was a Christian missionary and bishop active in Ireland during the fifth century. His own writings, especially the Confessio and the Letter to the soldiers of Coroticus, are the main surviving evidence about his life. He wrote that he had been kidnapped from Roman Britain as a youth and taken to Ireland as a slave before escaping and later returning as a missionary.
Medieval biographies added many stories, including the tale that Patrick drove snakes from Ireland. Historians generally treat that story as symbolic or legendary, since post-glacial Ireland has no native snake population. The shamrock story is also a later tradition, linking its three leaves with Christian teaching about the Trinity.
Patrick’s feast day is March 17 and is celebrated internationally, especially in Ireland and communities of Irish heritage. He is one of Ireland’s best-known patron saints, alongside Saint Brigid and Saint Columba.