Since the earliest days of Christianity, it has been a custom to celebrate the anniversary of saints' deaths. This allows Christians to honor the saint's accomplishments and also to celebrate their entry into heaven. A "feast day" is made for every saint, even when their date of death is unknown. It is sometimes said that St. Patrick's Day is celebrated because it is the day that the patron saint of Ireland, St. Patrick drove the serpents away from Ireland. More traditionally, it is the day when St. Patrick died. He died on March 17th 461 A.D. and his death has been celebrated ever since.