Board Thread:General Discussion/@comment-26872804-20150815160415/@comment-1600847-20150817120247

Well, he was born in High Rock, but that doesn't mean he's a Breton. For example, Annaig Hoinart was born in Black Marsh but she was a Breton, not an Argonian.

Given his first name (Hjalti Early-Beard) and how quickly the Nords pledged themselves to him, I'd say he was a Nord. Maybe he was half-Nord and half-Breton, or half-Nord and half-Imperial, who knows.