^lolwut? Interesting setup. I was expecting the mer- altmer, dunmer, bosmer. then the beasts- argonian, kajiit, orismer (yes I know, orcs are mer). then the humans- Breton, Redguard, Nord, Imperial.
The Dunmer
hate the Altmer (and, well, pretty much everyone really, but especially the Altmer), and the Altmer hate them right back. The Dunmer were originally a sect of Altmer (Aldmer?) who split off from severe philosophical differences, and became the Chimer. Then the whole Red Mountain/Dwemer thing where the Tribunal were born and betrayed Nerevar, where Azura cursed them to be Dunmer.
The Nords hate the Bretons, because Nords don't like elves and distrust magic and Bretons interbred with elves for so long they're more magically-natured.
The Nords, at least, have the whole honor thing and aren't that dikeish when push comes to shove and someone needs help. The Redguards, though, are quite prideful, and the Argonians are very isolationist (with a severe hatred for the Dunmer, particularly since they cut down a Hist tree).