St. Patrick’s Day is celebrated March 17, the date of Saint Patrick’s death in the fifth century. In Ireland this is both a national holiday and a holy day.
As the patron saint of Ireland, Saint Patrick was credited as the person who brought Christianity to the Irish. Although not a legal holiday in the United States, the day is recognized as a celebration of Irish and Irish-American cultures. It is estimated that about 39 million U.S. residents claim Irish ancestry. The day has been celebrated in North America since the late 18th century.