St.Patrick's Day

So St.Patrick's Day is coming up and I was wondering what it asctually was?? So i did some research and found out that it is the celebration of the Irish Saint, Saint Patrick, and March 17th (St.Patrick's Day) is the day he died in the 5th century! So that answered that question, but then I began to wonder why an Irish religious holiday was so widely celebrated in the U.S.?? So then I learned that in 1845, millions of irish fled to the United States during the Great Potato Famine, which they soon realized gave them a huge swing vote for politicians known as the "green party," thus beginning the tradition of wearing green. Soon, the Irish-Americans went from being made fun of and thought of as "crazy drunks running wild in the streets" to having their religious holiday being celebrated throughout the country. Attending St.Patrick's Day parades quickly became a must for all politicians hoping to be elected.