Board Thread:Lore Discussion/@comment-80.167.204.194-20150723072534/@comment-27913894-20160325150806

Given their ultimate ancestry and origins from the early Aldmer, they are, technically, still classified as Mer, given their name 'Orsimer' in the Altmeri tongue. However, it would seem as though they have lost their magical potency for some reason, and their unique appearance could explain why the other races don't initially recognize them as Mer. More so, their unique culture, weaponry, and abilities isolate them from almost every other subspecies of Mer on Nirn, with their closes relatives in terms of unique culture and abilities being, arguably, the Bosmer, or Wood Elves in the Imperial tongue. After all, a stereotypical or generic Mer is almost always known for their magical potency, arrogance, advanced culture, and overall appearance that arguably resembles your modern-day Altmer. Given these reasons, it's not unreasonable to think that anyone would mistake them for anything other than a unique subspecies of Mer. In the end, with enough knowledge of Orsimer, it is easy to recognize them as Mer simply by recognizing their 'elvish' ears and trademark arrogance that almost all Mer carry in one form or another.

Fun fact: Despite being considered a race of Men, some Bretons also carry the trademark arrogance of Mer due to their half-Elven blood.