As much as someone that is paying attention to lore would be initially inclined to cringe at races being in the "wrong" faction, they DID deliberately leave your character's past undetermined...
so, from a roleplaying standpoint, who's to say HOW your character got to where they were? NOW- that doesn't mean RPers won't react strangely.
Drizzt Do'Urden is a perfect example- when he fled the Underdark, he had a pretty hard time on the surface as people hated the drow (with good reason)- but... he was still there and once his renown got high enough, it became less of an issue with people that were familiar with the story behind the white haired dark elf with the mystical black panther running across Spine of the World killing orcs.
So, I would say from a RPing standpoint, as long as you have a lore friendly way for how you got where you got, it "makes sense", but, again, it doesn't mean you would be accepted or even comfortable and you would most certainly face some form of persecution.