Origins and Captivity
Patrick was born around 387, by tradition at Kilpatrick near Dumbarton in present-day Scotland; other proposed birthplaces include Banna (Birdoswald) on Hadrian's Wall in Cumbria, and locations in Somerset and Wales. He came from a Romano-British Christian family of standing: his father Calpurnius served as a decurion and deacon, and his grandfather Potitus was a priest. His mother Conchessa was said to be a near relative of Saint Martin of Tours. By his own admission Patrick was not religious in his youth, considering himself, in his words, idle and callow.
At the age of sixteen he was captured by Irish raiders and carried into slavery in Ireland, where he served as a herdsman for a chieftain named Milchu in Dalriada (present-day County Antrim). For six years he tended flocks in the valley of the Braid and on the slopes of Slemish. During this captivity his prayer life deepened greatly; tradition relates that he recited as many as a hundred prayers a day.
Escape and Formation
After a vision instructing him to flee, Patrick traveled roughly two hundred miles to the coast, boarded a ship, and after a three-day voyage and a long journey through wilderness reached Gaul, eventually returning to Britain. He then received a further vision in which the Irish people called him to return to them.
He pursued clerical training in Gaul, associated by tradition with Saint Martin's monastery at Tours and the island sanctuary of Lerins, and placed himself under Bishop Germanus of Auxerre, who ordained him to the priesthood. He afterward received episcopal consecration and, by tradition, was commissioned by Pope Celestine I around 432 for the Irish mission.
The Mission to Ireland
Patrick landed in Ireland probably in the summer of 433, by tradition at the Vantry River near Wicklow Head. His most famous confrontation took place at Tara on Easter Sunday, where he kindled the Paschal fire in defiance of the king's edict, processing in full episcopal vestments. He is traditionally said to have used the shamrock — three parts yet one plant — to explain the Holy Trinity to the chieftains, three divine persons in one God.
He approached the tribal chieftains for permission to evangelize, converting wealthy women and the sons of kings, ordaining priests, and establishing an episcopal administration of monastic character. In 445 he established his primary church at Armagh, which became the head church of Ireland. He also withdrew for periods of solitary prayer, spending forty days in fasting on Croagh Patrick and visiting the island of Lough Derg, which became a famous place of pilgrimage.
Writings
Two Latin writings are securely attributed to Patrick: the Confessio (Declaration), a semi-autobiographical defense of his mission, and the Epistola ad milites Corotici (Letter to the soldiers of Coroticus), in which he excommunicated a British king whose soldiers had killed and enslaved some of Patrick's converts. He also composed ecclesiastical canons together with the bishops Auxilius and Isserninus before 460.
The Lorica, known as the Deer's Cry or Saint Patrick's Breastplate (Faeth Fiada), a prayer of Trinitarian theology and spiritual protection, is also attributed to him by tradition.
Death and Legacy
Patrick died at Saul, Downpatrick, on March 17; the death dates proposed by various sources range from 457 to 461/2 and as late as 492/3. By tradition Saint Tassach administered his last sacraments. He was buried near Saul, where the cathedral of Down later arose, his remains said to be wrapped in a shroud woven by Saint Brigid.
Venerated in the Orthodox Church as Equal-to-the-Apostles and Enlightener of Ireland, Patrick is remembered as the principal evangelizer of the Irish and the founder of its episcopal church.
Relics & Shrines
Patrick is traditionally held to be buried at Down Cathedral in Downpatrick, alongside Saint Brigid and Saint Columba.
Saint Patrick's Bell (Clog Phadraig) survives in the National Museum of Ireland, encased in a shrine made for King Domnall Ua Lochlainn between 1091 and 1105. Lough Derg and Croagh Patrick, associated with his periods of prayer and fasting, became enduring sites of pilgrimage.