Saint Patrick was kidnapped and brought to Ireland as a slave. He lived there for several years herding sheep until his escape.  During this time he had become very prayerful and felt he was called by God . He returned to Ireland to spread  Christianity  throughout the land.  He traveled village to village.  To explain the concept of the father, son and holy ghost he used the shamrock showing the three leaves coming from one stem. Later in Ireland a day of thanksgiving was held to honour Saint Patrick.  It was in America at the end of the 19th century that the saint Patrick's Day Parade grew in importance. Saint Patrick didn't drive snakes out of Ireland despite the tale. Saint Patrick converted Ireland to Christianity in 432. Saint Patrick's cathedral in Dublin is 300 feet long. A church has stood here since the 5th century.  In 1191 the Norman's built a church here.  The present cathedral dates from the early 13th century.