Quote Originally Posted by The Scotsman View Post
Your position brings to mind the image of an American sports fan, dressed in a jersey of his favorite team. The sports fan isn't actually a member of the team - in most cases he has never even attended the college that the team plays for, but he likes to wear the jersey because (for whatever reason) he feels some sense of identity with that particular ball team, even though he isn't an actual member.
This is actually a more appropriate analogy than you might realize. There is evidence to support the theory that "named tartans" first arose among the Highland regiments. It makes a lot of sense -- the military being dressed in uniforms, which by definition must be uniform (all the same). So the soldiers would be outfitted in the same tartan, which would be the named regimental tartan. Many of the earliest references we have to regulated and named tartan designs are for military regiments.

Now, many of these regiments were closely affiliated with one or more clans. Think of the Black Watch's association with the Campbells, Grants and Munros. Think of the Seaforth's association with clan MacKenzie. The Gordon Highlanders have an obvious association with the Gordon clan.

And the "clan tartans" for each of the above named examples just so happen to have originally been designed for military use by the respective regiments (or, in the case of the Grants and Munros, the hunting tartan for the clan).

My theory is that these tartans came to be regarded as "clan tartans" because they were being worn by people in the clan outside of the military, most likely in a show of support and solidarity for their boys in uniform.

In other words, much like a sports fan may wear the colors of his favorite team, even though he is not actually on the roster.