I would compare them to refugee Romanovs, or members of some other aristocracy that no longer exists. They are still arrogant and have elevated ideas about themselves, but they're not very numerous and nobody else cares. I see them pretty much forced to deal with other races of men, and not very happy about it (much like those same Romanovs and other so-called "royals" when forced to deal with peons, peasants, and assorted hoi polloi such as ourselves).
There may also be some pure enclaves of Hyperboreans hidden in (for example) the Spiral Mountains, but I doubt those are very numerous. It could make for an interesting adventure - perhaps such an enclave has gotten their hands on an ancient magical or technological weapon and is planning to turn it on Khromarium ("If we can't have it, no one can!").