First of all, Saint Patrick was born in Britain. When he was 16, Patrick was kidnapped by Irish raiders and was thrown into jail and stayed there for 6 years. After he was released, Patrick converted to Christianity and decided to be a Christian missionary. So, Patrick spread the good news all around Ireland. They say that he chased away the ‘snakes’ (pagans) because he wanted to preserve Christianity. Patrick used his holy staff to chase away the pagans. Saint Patrick used a shamrock a an example as the holy trinity.
The first Saint Patrick’s day parade was in America in 1762 when Irish soldiers marched to a tavern in Manhattan. Today it is the largest and longest parade in America.