Why is the football team Notre Dame called the Fighting Irish when the cathedral Notre Dame is in France?

The school was founded by the Jesuits, the Order that was founded by St. Ignatius De Loyola, the only known Saint to have a notarized criminal record in Spain for public brawling and intoxication. At the turn of the Century, in America particularly, the Mid-Atlantic and New England regions were dominated by Protestants and other Christian denominations more hostile to the Papacy. Upon mass migration of Irish to America, the Word Catholic became synonymous with Irish.