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Snow Elf - The Elder Scrolls Wiki
"The
Snow Elves were a
race of
mer who inhabited
Skyrim long before the
Nords. It is commonly believed that centuries of underground living and
Dwemer slavery twisted the race into the blind merciless
Falmer. Amongst the few Snow Elf survivors, they prefer the name Snow Elf over their original name of Falmer, as it tends to refer to their now degenerated brethren, which the survivors call The Betrayed."
The truth is, no one is completely certain exactly what happened to the Dwemer, and Snow Elves/Falmer. It all happened long ago, and underground, where there were no witnesses. There's also no surviving records, so all we have to go on is the facts. The Nords returned from Atmora, and drove the Snow Elves beneath the surface. Now, the survivors are the blind twisted Falmer. Insisting your assumptions trump my assumptions do not make you right, and me wrong. THAT is the Lore.