Snow Elf

"In the time before man, they were known as the snow elves. They lived in the sunlight and had a very prosperous society."

- Enthir

The Snow Elves were a race of elves who inhabited Skyrim long before the Nords, before centuries of underground living and Dwemer slavery twisted the race into the blind merciless Falmer. Not much is known of their origins, it is possible they were a hybrid of other Elven races. They were led by a Snow Elf known only as the 'Snow Prince' who led them into a genocidal campaign against the first humans in Tamriel, the Nords of Nede lineage that had immigrated to Skyrim from Atmora. The Snow Prince was slain by a child at the battle of Moesring. Due to the death of the Snow Prince, the elves' hope was shattered and some fled the battle. It's not known what the exact date was, but it was sometime at the start of the second Era. The Nords then mounted a reprisal campaign and killed Snow Elves by the thousands. The Snow Elves retreated underground where they found refuge with the Dwemer. The Dwemer betrayed the Snow Elves, however, force-feeding them a toxic fungi that inflicted blindness. The poisoning effects of the fungi caused the Snow Elves to devolve into the twisted beings they have become, the Falmer.

Physiology
One visual representation of the Snow Elf is known to exist and is located in the Irkngthand Sanctuary. It is a very large statue depicting a Snow Elf holding a book and staff, wearing a headpiece and ceremonial-looking clothing. This elf looks different from all known elven races (Altmer, Dunmer, Orsimer, and Bosmer) as its head and eyes are smaller, much like a human, and it is likely they had white skin as the Falmer do, although that might not be the case since the Falmer's skin color may have changed due to lack of exposure to light.

The Falmer of Skyrim somewhat mirror the Goblins from The Elder Scrolls IV: Oblivion.

Behavior
There is speculation that the Snow Elf will eventually become a surface-dwelling race once again as there have been reports of more and more organized surface raids of Falmer attacking cattle and crops for food. Ursa Uthrax (the author of the in-game book The Falmer: A Study, obtainable in The Elder Scrolls V: Skyrim) fears the rise of the Falmer, writing, "I fear a horror neither man nor gods could possibly stand against." This indicates a recognition of the prowess of the Falmer.

Disappearance theories
It could also be true that the Falmer are the reason for the disappearance of the dwarves, though all of the Dwemer disappearing at the exact same time highly discredits this theory. This theory is also further refuted by the book Battle of Red Mountain which contains the transcript of Lord Vivec recounting of the events surrounding the disappearance of the Dwemer.