Terncliff & Raen Au Ra

[Astralia]

I'm digging this up !
From what we know, Raen originated in the Azim's steppes as well, contrarily to the Xaela, they just left. Anywhere they might have went to they were first received with hatred by the other races in the early years. Eventually they were welcomed well by some Yanxia warlords who recognized their value as warriors and some other were hired as retainers. They gained their citizenships quite everywhere bit by bit I'd say. In the meanwhile, a group ultimately settled in the Ruby Sea foundind the now-well-known Sui-no-Sato town decreting they shouldn't involve with other races and the world's affairs, aside commercial exchanges that transit via Tamamizu.

So, in the end most Raen live in Doma and its surroudings, one group settled in the Ruby Sea, however it's not so farfetched to think other groups of Raen crossed the sea to establish around Kugane (Though I can't remember of any NPC being a Raen in Kugan for example but lore-wise/rp-wise it wouldn't be that wrong to think that) or other groups that fled towards Nagxia and Ilsabard regions, especially on the Werlyt coast and some fewer Raens going deeper into Ilsabard and rejoining the surroundings of Ghimlyt dark near Eorzea. Plus, as seen in the Werlyt storyline quests, some Raen enrolled into the Garlean army, either willingly or by force.

EDIT : Indeed there's some Raen NPC in Kugane, some giving side quests such as the timid girl up the market alley