re: Game of Thrones S4:E6:"The Laws of Gods and Men", HODORS ONLY (no book readers)

Dorne is the southern-most region of Westeros. It's like the region that has its own norms and doesn't follow in lock step with the rest of Westeros, but is still part of the 7 kingdoms. (like Texas, perhaps). I think it is well established with Oberyn's dialogue that those from Dorne know they do things differently and are looked down upon. Oberyn has been passively insulted a few times by Tywin and Cersei in previous episodes.

Braavos is across the Narrow Sea.