This is just misinformation. Slavery is apart of Dunmer society, but it wasn't built on it. This will just turn into another pissing contest between Dunmer and Argonian fans though.
*pees on Lord Tidus*
FOR BLACK MARSH, DUNMER SCUM!
As for the OP, the nords don't like mer in general. They tolerate dunmer at best, as they've been hard hit, but the nords do not like how they were shoved out of Morrowind in the first era. They abhor altmer, because of religious differences and the fate of the world. As for bosmer, well they're weird mer.
As for dunmer, expect some forms of resentment against the nords, at least those who were in the Great Houses, as they're being sheltered by the enemy. In addition, expect the dunmer to give the stink eye to argonians, for obvious reasons.