Saint Patrick's day is celebrate as an important Catholic feast day in Ireland. It also has important religious significance in other places that recognize the importance of Saint Patrick in bringing Christianity to Ireland. While the story of Saint Patrick does relate to the bringing of Christianity to Ireland, many of the stories and celebrations have other influences and reasons that have shaped the celebratory day.
Saint Patrick's day only became a recognized feast day in the early 17th century. However, it's development and traditions took various forms of influence.