Why is st Patrick recognised as a saint?

Saint Patrick is recognized as a saint for his efforts in spreading Christianity throughout Ireland in the 5th century. He is credited with using the shamrock to explain the concept of the Holy Trinity to the Irish people and for driving the snakes out of Ireland, which symbolizes the conversion of pagans to Christianity. His feast day, St. Patrick's Day, is celebrated on March 17th each year in commemoration of his life and legacy.