Somehow I feel compelled to mention this every St. Patrick’s Day. I’m at least a quarter Irish and possibly as much as half Irish. After fifty years of genealogical research that’s as specific as I can be. I have two parents, four grandparents, and eight great-grandparents, just like most people. Of my four maternal great-grandparents at least two were Irish and one may have been half Irish. My best guess if that the other great-grandparent was mostly French (it’s possible that half Irish great-grandparent was Irish and French, too).
My best high school buddy, among the most Irish Americans I know with four grandparents all born in Ireland, used to wear orange on St. Patrick’s Day in protest.