Wallace T. and brooklyn dave have given you good answers, but as the proud son of Ulster-Scots settlers in Ohio, I can give you a little more.
Before they were "planted" in Ulster to pacify and displace the native Irish Catholics, these people came from the borderlands of Northern England and lowland/southern Scotland, which has always been a very troublesome and ungovernable region.
These "Borderers" or "Reivers" had a tradition of raiding other clans for livestock, women and other booty. As a result, they have a long history of family feuds, reflected in the unpleasantness between the Hatfield and McCoy families (both of whom were of the same stock.) Their culture by necessity inculcated a skill with horse, sword, and gun that may explain their later prominence in military service.
In religion, they were strong anti-Papists and anti-establishmentarians. They subscribed to the Scottish Covenant of the 1600's, which gave rise to the Presbyterian Church and influenced other Dissenters and Reformers such as the Methodists.
By eviction, subsidy, and persuasion, they were settled in Northern Ireland in the late 1600's and 1700's. There, from the point of view of the English King and his bishops, they would be less of a threat to the Crown and established Church of England, and a bulwark against the even worse Irish Catholics.
They were mostly tenant farmers under the thumb of the Anglican nobility, including my own people, who labored on the estate of Lord Montjoy in Omagh. They proved to be as stubborn and warlike in Ulster as they did in the Border Country, thus suffering significant repression at the hands of the Crown and Church, and so in the second half of the 1700's and first half of the 1800's, great numbers of them emigrated to the US.
However, when they arrived, they found some of the same discrimination they had left behind in Ulster. The Anglicans of the South and the Puritans of the North wanted little to do with them. The settlers had to continue on to the backwoods and frontiers to find the liberty they so fiercely craved. From western Pennsylvania, to Ohio, Kentucky, Tennessee, West Virginia, and so on down the Appalachians to northern Georgia and the uplands of the Carolinas, they became the majority. Their Calvinist Presbyterian faith evolved, and many became Methodists, Baptists, or Pentecostals and remain so to the present day.
Their culture survives in the folkways of the Appalachian hillbillies, and much of what is now perceived as Southern speech and manners would be recognizable to an archaic Border reiver of 1600 or so. Most notably, there is a very high premium placed on a man's honor and reputation, and a very low threshold for violent defense of that honor.
Great numbers fought on both side in the Civil War, and the culture gave rise both to eloquent abolitionists and vicious racists. In the Deep South, they were seldom wealthy plantation owners, and more often among the poor white "crackers" and "rednecks". These words reflect their Scottish heritage: "cracker" probably comes from the Gaelic word "craic", meaning bantering, bragging, and boisterous conversation, while "redneck" refers to the Scotch Covenanters who signed the Covenant in their own blood and subsequently wore bloody rags on their necks to signify that fact.
If you find this stuff interesting and wish to learn more about the Scots-Irish, you should look up a book called "Albion's Seed", by David Hackett Fischer. Webb's book is supposed to be good too, but I haven't read it yet.
(In before the "Albion's Seed" reference.) See my post directly above yours. Your post was very informative and interesting.
An interesting phenomenon is when you are driving from Nashville into east Tennessee on I-40, or go north of Atlanta on Highway 400, or south from Pennsylvania on I-79, you begin to hear bluegrass oriented radio stations along with standard country music fare. On Sundays, you can hear old time Gospel music and even sacred harp type singing along with loud and emotional Pentecostal style worship. Appalachia is clearly different from either the North or the Deep South.
Thank You for the info.
My Great great grandmother was Scottish, they say she came from Ireland. Wondering now if she was an Ulster Scot? Have you any knowledge or info on the last name Adams. Would be greatly appreciated.
Very good and informative post!! Keep on trucking!!!