On my father's maternal side of the family, is Irish ancestry. To me this day is a day of fun...When I was younger, I used to be a part of the St. Patrick's day parade in my home town. It was always freezing cold and I remember having far too many Irish coffees to keep warm and suffering later may you have the luck of the Irish.
As I known, that the St. Patrick's day has been a traditional day for Irish a long long time ago, this day also as important as the national day of Ireland.