A better book on the Appalachian migration is “Born Fighting” by Jim Webb.
It is on my shelf, read several times and copiously underlined, as is How the Scots Invented the Modern World: The True Story of How Western Europe's Poorest Nation Created Our World & Everything in It by Arthur Herman, which is also great background about the Ulster Scots migration into the U.S. And let's not forget Thomas Sowell's incisive Black Rednecks and White Liberals.