[Morris at Heathfield]

By "dark" tartans, do you mean tartans in the "modern" colors? These colors date back to the mid-19th century when chemical dyes were developed which eventually replaced the vegetable dyes. The vegetable dyes were generally lighter in hue than the chemical dyes that replaced them. The "ancient" colors are an attempt to reproduce the old vegetable dyes—or at least, what those dyes looked like after a hundred or so years of fading. The split between "modern", "ancient", and "weathered" tartans only goes back a half-century or so. Peter MacDonald has a good article on the subject here.

Or, by "dark" tartans, do you mean tartans in "dark" colors such as black, blue, and green? If so, then I would be interested in learning Scarlett's theory behind their origin. 18th-century portraits of Campbells wearing tartan usually show them wearing red and black tartans and, from what few portraits I have seen, black-blue-green tartans do not seem to have been worn by anyone except members of the Black Watch during the 18th century, but I have wondered if such tartans are what Scarlett meant when he referred to the "MacDonald type" of tartan here.

[sirdaniel1975]

Originally Posted by Morris of Heathfield

By "dark" tartans, do you mean tartans in the "modern" colors? These colors date back to the mid-19th century when chemical dyes were developed which eventually replaced the vegetable dyes. The vegetable dyes were generally lighter in hue than the chemical dyes that replaced them. The "ancient" colors are an attempt to reproduce the old vegetable dyes—or at least, what those dyes looked like after a hundred or so years of fading. The split between "modern", "ancient", and "weathered" tartans only goes back a half-century or so. Peter MacDonald has a good article on the subject here.

Or, by "dark" tartans, do you mean tartans in "dark" colors such as black, blue, and green? If so, then I would be interested in learning Scarlett's theory behind their origin. 18th-century portraits of Campbells wearing tartan usually show them wearing red and black tartans and, from what few portraits I have seen, black-blue-green tartans do not seem to have been worn by anyone except members of the Black Watch during the 18th century, but I have wondered if such tartans are what Scarlett meant when he referred to the "MacDonald type" of tartan here.

They were completely capable of developing dark colored tartans with vegetable dyes. I met a Lass at the STM who dyes wool herself using traditional techniques and natural sources to dye wool. She very quickly explained how simple it was to get as bright or dark a thread she desired.

Here's an interesting article on the Black Watch tartan: The Original Military Tartan

[Morris at Heathfield]

Perhaps I should have bothered to read Scarlett's article in its entirety again, rather than just the part I thought was pertinent to my post. In the last paragraph of the Background section, he says what he calls the "MacDonald type" is "predominantly red", and "has a broad green stripe with a narrower black or blue one [sic] each side...." That sounds something like the MacDonald of Sleat tartan, rather than the conventional clan tartan (which is not attested before 1810). There's another article by Scarlett here. It's briefer, but it has more to say about the origin of clan tartans. The other part I missed was Scarletts opinion that the "dark setts" (blue-black-green) originated either with the military or with George Buchanan. That's not much different from what I had supposed.

Originally Posted by sirdaniel1975

They were completely capable of developing dark colored tartans with vegetable dyes.

Yes, they were. However, as a general rule, the green—at least—of the tartans produced before the mid-19th century was quite lighter than the green of the tartans produced in modern colors. Other colors also tended to be somewhat lighter, although not nearly so light as the modern "ancient" tartans. I'm not sure why it changed. It may have to do with Victorian tastes in color, or it may be that early chemical dyes had a limited (dark) palette. Obviously, chemical dyes can produce all sorts of shades these days, since they're used for the "ancient" and "weathered" tartans as well as the "modern" tartans.