From all that I have read, the kilt IS distinctly Scottish (and I would have it no other way!)...but during the Victorian era, there was a sort of highland revival, and people who originally had nothing to do with kilt wearing got in on the craze. As far as I can tell, there is no difference in construction, just different tartans (many of which are very nice patterns). For more information you can check out Matt Newsome's site www.albanach.org. He has a number of really well written articles on there.