Elder Thing, by Ridureyu
The “Elder Things” from H. P. Lovecraft’s “At The Mountains Of Madness” are one of the very first Ancient Aliens/Astronauts to show up in literature!
Long before the human race even began to evolve, the Elder Things travelled from a distant star to our planet. They built an amazing civilization, with ruins that could withstand even a billion years of emptiness. Within their massive, ornate cities, they also created the amorphous Shoggoths as a race of slaves, servile creatures to do their bidding.
The Elder Things ruled in eace until Cthulhu and its Star-Spawn invaded, setting off the first major war in Earth’s history. Amazingly, they were able to fight off Cthulhu, until the ancient One retreated to sleep beneath the waves in his city of R’yleh. The Elder Things then came into conflict with the Mi-Go and even the Great Race of Yith, still surviving each conflict until they were finally at peace again. But this, too, did not last, as the Shoggoths gained minds of their own, and soon rebelled against their masters. The civil war with the Shoggoths was the most brutal one yet, and the Elder Things nearly destroyed themselves in order to subdue their Shoggoths again. And yet, after surviving so many wars, their time was running out – the first great Ice Age came, and this spelled the doom of the Elder Things. Survivors had to flee their great cities or die, with a few remnants settling beneath the ocean, in an environment that could sustain them. But soon, even their cities were overrun by rebelling Shoggoths.
There are hints that the race is not entirely extinct in the Cthulhu Mythos, and at least some survived frozen long enough to be revived (temporarily) in At The Mountains of Madness. But for the most part, the Elder Race is long gone, leaving only a few scattered ruins and the monster Shoggoths as evidence of their once-great society.