asked: "The Dornish are not based thoroughly and exhaustively on "Arabs, Turks and Iranians" according to Martin. BTW the North strikes me as Scottish or northern English at the very least (not in Martin's words but neither is "Arabs, Turks, and Iranians"), but clearly not all northmen were cast with actors from those areas."
Very good point also. And there’s the whole messy question of nationality vs. ethnicity and so on.
edit: I said nationalist instead of nationality. Hmm.