Specifically, it celebrates the arrival of Christianity in Ireland.
The Feast of St. Patrick, commonly known as St. Patrick’s Day, is a cultural and religious holiday in Ireland. Each year, this holiday is celebrated on March 17th. This holiday celebrates Saint Patrick, who is the most recognized of Ireland’s patron saint. Specifically, it celebrates the arrival of Christianity in Ireland. Saint Patrick played a prominent role in bringing Christianity to Ireland from Roman Britain during the fifth century AD.