Oh, yes, the Nack MacFeegle are definitely supposed to be Highlanders (if you allow for the fact that their skins are blue and they only stand a few inches tall!).
They swear like Gleska keelies (at any rate, that is my impression based on reading Pratchett and George Macdonald Fraser’s recollections of his time as an officer in a kilted regiment at the tail end of the Second World War). And they wear a tartan that includes a fair amount of red.
My son is a fanatical Pratchett fan with a large collection of his books. I am not so keen on most of the Discworld novels, but I do have a soft spot for his series about the young witch Tiffany Aching, who is befriended by the Wee Free Men in the first of her stories and who keeps their loyalty (such as it is) through to the most recent of the tales I have read.
Oh, and since Pratchett was made a knight in 2009 he may be called Sir Terence or Sir Terry – but never Sir Pratchett.
Glad to find another fan o’ the Feegles!
Regards,
Mike