The shaded areas in the map above show where Scots-Irish settled and became the dominate ethnic group.  These areas also represent where Scots-Irish are still found in large numbers in the 21st Century.  The Appalachian area contains a core Scots-Irish area and runs from West Virginia down to the Mississippi Hill Country.  There are two other core Scots-Irish areas, east Texas and the Arkansas mountains, both the Ozarks and Ouachitas.