Oh the ecstasy! This is actually my undergrad thesis!

/u/truethomas and /u/lngwstksgk hit on some very good points. One shouldn't overgeneralize and also the '45 Rising/Culloden had a very strong impact on their society and livelihood.

Moving along, then, to the area in which I have less familiarity, many Jacobite families in the Highlands stood in danger of being "attainted"--that is, their blood declared unworthy such that no descendent of theirs could ever hold land or public office (note also that there are Jacobite descendants who today remain attainted, though this has no real legal meaning any more from what I understand). Transferring their allegiance to the Georgian army or providing other services to the Crown is one way in which they could rehabilitate themselves, so to speak. This was also facilitated by the Duke of Argyll, First Minister for Scotland, who capitalized on London's conceptions of the Highlander as being clannish and violent to suggest that only certain people to whom the populace was "especially loyal" could be trusted to tame these violent instincts for Britain. Those certain people, of course, often just happened to be well-born former Jacobites in need of some good PR. (More on this can be found in Andrew McKillop's More Fruitful Than the Soil, which I believe might also go into more detail on this area.)

Using /u/lngwstksgk's as vehicle to segway into the Seven Years war for a brief moment here. Before the '45 Rising, Independent Highland companies had been created to "police" the Highlands and create a standing army for Britain to use, the Black Watch or then 43rd Regiment of Foot was such an example. As mentioned above the Dress Act of 1746 took away the Highland Dress and forbid them to be armed. Hanover crushed the Highland culture with banning tartan, Gaelic, and possessing arms in one fell swoop, and the only legal way a Highlander could continue his traditional martial prowess and wearing of the tartan was to join the Highland regiments of the British army. Otherwise, Highlanders emigrated from Scotland to mainland Europe as mercenaries or to the New World: North America and the Caribbean.

The Seven Years War offered Highlanders the opportunity not only to be martial and clad in plaid, but to show their worth to the British Military and make amends to British society. Both Former and non-Jacobite Highlanders did this. A large portion of Highland regiments during the SY War had former Jacobites in their ranks. Highlanders were at first used as "cannon fodder" for the other regiments, but after several battles and tests of battle expertise they became recognized as superior troops and highly disciplined. After the Seven Years War, Highlanders became integrated in the military and arguably British society, but this still isn't the full reason for Loyalism.

Let's look at North Carolina now. Highlanders had been immigrating to North Carolina as early as 1732 and settled into the Cape Fear River area, modern day Fayetteville. They settled into what was then known as Cross Creek and Campbelltown as their own separate community inside Cumblerland county. Highlanders even got to elect their own representatives in the General Assembly to show how numerous they were in Cumblerland. In a way, Campbelltown reflected their old clan system with having a landlord and higher representative as a "chief" or officer. The very few primary sources available have said that they spoke Gaelic as their main language, only a few educated ones were bi-lingual. Campbelltown acted like a Scottish "Little China" with Gaelic language spoken, Gaelic churches (A big part of their lives), and their traditional culture. I do not know how armed or if they wore tartan in NC, but their are sources saying that many Highlanders that arrived on boat scared the population because they were dressed in tartan and armed to the teeth. Highland immigration boomed in the later 1760s and early 70s, and even up to the outbreak of the war.

Before 1776, Highlanders were only used in the Battle of Alamance to put down the Regulators, although it is debatable on whether they fought in battle or not. Not only were Highlanders integrated into British military but those in NC became part of NC and this is where the trouble began.

Once the Provincial governments, assemblies, and the Committees of Safeties started to appear, any person tied to reputations as Loyalists were viewed under suspicion and Whigs sometimes acted violently towards Loyalists. Loyalists faced possible land confiscation, forced conscription into a NC militia, and even began barred from commercial interactions. It didn't help when Governor Josiah Martin used several Highland community leaders to recruit for his Loyalist army and put Highlanders in the spot light. Sources I have read said that most of the Highland population in Cumberland wanted to be neutral and stay out of the Whig v. Loyalist affairs. Obviously, the Highland recruiters gathered a number of Highlanders to join the newly formed Loyalist army (See Battle of Moore's Creek and the Royal Highland Emigrants). Just to note, both sides actively tried to get the Highlanders on their side or in the Whig's case: neutral. The provincial government sent over about 12 delegates (several with Highland last names) to appeal to the Highland community to join the Whig cause or at least be neutral.

Clans like the Campbells were solid Whigs.

Actually, from the source I have read but I do not have on hand at the moment, Campbells largely supported the Crown and have seen numerous surnames in Loyalist Muster Rolls with Campbell.

A bit personal here, but my thesis claims that they were coerced into loyalism like many of the backcountry loyalists. Previous historians have argued from "obedience to community leaders" such as the Highland recruiters, fear of land being taken away if didn't join the Whigs, and even Oaths of Allegiance to the King, which were taken before they received their land grants. There is also the idea that Highlanders wanted to use military service to gain land grants like how the Seven Years war had the Royal Proclamation of 1763. These factors are a bit simplified and overgeneralizing to the point of making the Highlanders seem like they are thoughtless Loyalist yes-men. Putting them into the context of NC, I see "fear of losing land" as a high possibility, but I've expanded to include that they also feared the coercion and antagonism from the revolutionary government in NC. That part, I am personally still working on, so while I believe it is supported, you may take it with a grain of salt.

Bibliography:

Colonial and State Records of North Carolina. Ed. William L. Saunders (Raleigh, 1886-1890). 10 Volumes

Demond, Robert O. Loyalists in North Carolina During the Revolution. Durham: Duke University Press, 1940.

Dziennik, Matthew. "Through an Imperial Prism: Land, Liberty, and Highland Loyalism in the War for American Independence." Journal of British Studies 50 (2011).

Ekirch, A. Roger. Poor Carolina: Politics and Society in Colonial North Carolina, 1729-1776. Chapel Hill: University of North Carolina Press, 1981

Lee, Wayne E. Crowds and Soldiers in Revolutionary North Carolina: The Culture of Violence in Riot and War. Gainesville: University Press of Florida, 2001

Meyer, Duane. Highland Scots in North Carolina, 1732-1776. Chapel Hill: University of North Carolina Press, 1961

Newton, Michael. “Jacobite Past, Loyalist Present.” Journal of Interdisciplinary Celtic Studies 5 (October 2003): 31-62

First off, I forwarded this thread to another user that I know focuses more on the Highlanders in North America than I do.

However, I've read a little bit about this and would like to add some information to what truethomas has already mentioned. He or she is correct that any attempt to claim "all Highlanders" felt or acted one way is going to be wrong and that the Jacobite conflicts are often miscast in various A v. B styles that are equally wrong. However, where this user suggests you are thinking of the Clearances when you refer to "destroying their way of life" is overlooking the Harrying of the Glens. The aftermath of the Battle of Culloden was brutally violent and left some people too afraid to even bury the dead for fear of reprisal. Acts such as the Dress Act 1746 and the Act of Proscription (19 Geo. 2, c. 39, same year) very deliberately set out to crush identifiable aspects of Highland culture, including wearing the tartan, speaking Gaelic, and possessing weapons (London saw the Highlands as possessing a particularly "martial spirit", so this is relevant).

Moving along, then, to the area in which I have less familiarity, many Jacobite families in the Highlands stood in danger of being "attainted"--that is, their blood declared unworthy such that no descendent of theirs could ever hold land or public office (note also that there are Jacobite descendants who today remain attainted, though this has no real legal meaning any more from what I understand). Transferring their allegiance to the Georgian army or providing other services to the Crown is one way in which they could rehabilitate themselves, so to speak. This was also facilitated by the Duke of Argyll, First Minister for Scotland, who capitalized on London's conceptions of the Highlander as being clannish and violent to suggest that only certain people to whom the populace was "especially loyal" could be trusted to tame these violent instincts for Britain. Those certain people, of course, often just happened to be well-born former Jacobites in need of some good PR. (More on this can be found in Andrew McKillop's More Fruitful Than the Soil, which I believe might also go into more detail on this area.)

I hope that helps to shed some light on the background to the American Revolution and Highland Scottish loyalties, even if it does not directly respond to what you asked.

It's inaccurate and a major oversimplification to think that Highlanders were opposed to the 'British'.

The history of relations between England and Scotland, and between the Highlands and the Lowlands of Scotland is very long and very complex. Often religious and political differences mattered a lot more than national or cultural differences.

For example, several of the highland clans fought against Bonnie Prince Charlie and on the side of the government in the Jacobite uprising of 1745. And a good majority of the Scottish population were opposed to Prince Charlie. They did not want a Catholic king.

When you mention 'destroying their way of life' you seem to be thinking about the Highland Clearances. That had a lot less to do with the English than with lowland Scots, and with highland lairds who found it more profitable to get rid of tenants after the destruction of the Clan System. But the major highland clearances only took place after the American Revolution.

Even to say that Highlanders tended to be royalists would be too much of a generalization. Clans like the Campbells were solid Whigs.

The only real answer to your question is to suggest that you read up on Scottish history. You may find that it's a lot different, and a lot more complicated than you thought.