I've always thought about Attolia as red and black as I think those colours represent strenght and a certain ruthlesness, which would suite Attolia. And I've thought green and gold as Eddis: a benevolent yet strong leadership. Then blue and gold for Sounis (darker blue for the previous Sounis, lighter for Sophos) for royalty.

But yes, I think my colour association comes mostly from what Attolia and Eddis are wearing: Attolia's red and Eddis's green outfits. And I associate Sophos with a light sky blue on the Thief for some reason.

Maybe I should have a re-read (once again) and see where all of these associations are coming from!

Not that I'd need an excuse for reading the books again... It's just that when I start I read them all in a continuous flow and never get anything else done meanwhile. xD