Gelmorra was a refugee community composed of Elezen and Hyur who once made up the city-states of Eorzea that were driven underground by the Elementals after the War of the Magi twisted and corrupted the aether of the land. The Gelmorrans worked hard to turn their new home into a thriving underground metropolis until the day they would be welcomed above ground once again.
After the War of the Magi caused the Calamity of Water, the Elementals were angered by the survivors for the part they played in causing the balance of aether to be thrown so horribly out of alignment. The Elementals began attacking the Elezen who made their home under the boughs of what is now known as the Black Shroud. At the same time, a large migration of Hyur made their way to Eorzea and encroached on the land. Both groups were driven to hiding underground by the raging Elementals, and with no way to commune with them, were forced to band together to survive. Though the Hyur and Elezen initially engaged in warfare for ownership of the caves, resources became so scarce that they had no choice but to band together or die.
Building a Home
The Gelmorrans knew they would not survive by heading back to the surface without the ability to speak to the Elementals. With food and supplies being scarce, the Hyur and Elezen people worked together to tunnel further underneath the Black Shroud into the natural caves and tunnels that existed around the land. This let them gather precious resources to survive, and soon Gelmorra became a thriving colony.
Returning to the Surface
After several hundred years, the Ixal were suddenly cast out of the Twelveswood. Though the reason remains unclear, the belief is that the Ixal expanded their territory in the forest without the blessings of the Elementals. The Gelmorrans saw this as their opportunity to vie for land above ground. Those who were well versed in magic were gathered, and worked together to reach the Elementals through their arcane craft. Eventually, after much perseverance, the Gelmorrans were able to reach the Elementals. They were able to strike a bargain: As long as the Gelmorrans and their lineage would defend the forest, they may call it home. With that, the Gelmorrans returned to the surface and began building a new home. They christened this new city-state Gridania.
Though most of the Elezen and all of the Hyur left Gelmorra for the lands above, some of the Elezen felt betrayed by this abandonment of their home, and chose to stay behind. Though eventually these people would be lost to time, the ruins of Gelmorra can still be accessed, with some parts, such as the Mun-Tuy Cellars still in active use to this day.