Re: Thank you, both of you. (m)
It's a long time since I saw the film but Hollywood directors aren't always that careful about checking facts and I would guess it was just supposed to have a general medieval feel to it rather than specifically Scottish or even Celtic.
Wales may be at the opposite end of the country but Welsh and Gaelic are both Celtic languages and have a common root. (Welsh is what's called 'P' Celtic, whereas Gaelic is 'Q' Celtic).