Without too much spoilers, as you don't seem to have read it, Infernal City took care of them. they're all gone.
Spoiler Morrowind is completely destroyed, either by MoT impact, Red Mountain Exploding due to MoT, or Argonians invading. There may be a few stray Ashlanders that escaped, but I highly doubt it, being so far from civilisation.
Although, the temple became more to it's roots with the impact from the Nerevarine, so they may have went to join the temple.
Speaking pre-Infernal City, though, there prbably was other camps dotted around Vvardenfell, though. The in-game representation of Vvardenfell was far off scale, it's roughly the size of Australia, I believe. Or was that Daggerfall? I don't know. Either way, there would have been tons of ashlander camps, and the main ones would have been a lot larger than they are in game.