St.Patrick was born 387 AD and died the 17th of March 461 in Banna Venta Berniae, Britain. Calpornius, his father was a deacon, his grandfather Potitus a priest. When he was about sixteen he was captured by Irish raiders and taken as a slave to Ireland, where he lived for six years before escaping and returning to his family. He entered the church. He later returned to Ireland as a missionary in the north and west of the island, but little is known about the places where he worked and no link can be made between Patrick and any church. By the eighth century he had become the patron saint of Ireland.
St. Patrick is said to be buried at Down Cathedral in Downpatrick, County Down, alongside St. Brigid and St. Columba, although this has never been proven. The Battle for the Body of St. Patrick demonstrates the importance of both him as a spiritual leader, and of his body as an object of veneration, in early Christian Ireland.
Patrick came up with the clever analogy between the three leaves of the shamrock and the Holy Trinity. At any rate, this lesson is one explanation for why St. Patrick is associated with a shamrock. St. Patrick is also credited with driving the snakes out of Ireland. There were probably no snakes in Ireland for him to drive out, and it is very likely that the story was meant to be symbolic. Since Patrick converted the heathen, the snakes are thought to stand for the pagan beliefs or evil.
While we don't know exactly when he was born or died, this Roman British saint is honored by the Irish, especially in the United States, on March 17 with parades, green beer, cabbage, and corned beef.