Let me add my two cents worth. Several members of my family, who were born in Ireland and never lived in Scotland, came to the United States in the early 1900s. U.S. Census records list their nationality as Irish/ Scotch. My theory is this: There was great prejudice in the United States at that time against the Irish and particularly against Irish Catholics. One had a better chance of making a living if he was Protestant. It was because of this prejudice that the term "Scotch Irish" came into common use. Bill O'Neil.