The Separation of Aefareth
The Separation of Aefareth refers to creations of Felhedell and Northumbria, and the distinctions made between the two of them. It comprised of the formation of the Aefarethen Mountain range and the changing of the land of Felhedell.
Manifestation
The separation of Aefareth manifests in the total destruction and change of the lands of Felhedell and the creation of the mountain range that now splits the two lands of Felhdell and Northumbria.
Prior to the separation, Felhedell was previously referred to as Northern Aefareth, and was a lush and fertile land, covered in thick vegetation and dense forests. It was a beautiful land, and well suited for being settled on. When the people of Southern Aefareth started to settle on the land and build towns and villages, some small groups of them decided to spread further north and make their homes there. However, once there, they chose to ignore the prior warnings of the earth's spirits to the settlers in the south, and they built their settlements without respecting the earth - they cut down trees and tore up the land to make space for their homes, but did not pay the due respects owed to the land in return.
Therefore, the earth's spirits made good on their promise to make the settlers pay for their disrespect - they used their ancient and powerful magic to change the land, turning the fertile soil into barren wastelands and freezing glaciers and scorching deserts as punishment, and the creatures of the land were turned into monsters who hunted the settlers.
The elves did not wish for the monsters to spread and encroach on the kingdoms formed in Southern Aefareth when the settlers there had respected the wishes and desires of the earth's spirits, and so Arcane Elves from Lyalume worked together with the Earth Elves from Naenlune to magically form the impassable mountain range that bisected the continent and separated the two halves.
Southern Aefareth then became known as Northumbria, or the Safe Lands to the people of Felhedell, and Northern Aefareth became known as Felhedell, or the Northern Lands to the people of Northumbria. Since then, the two parts of the continent have ceased all contact with one another, and Northumbria is, for the most part, unaware of people living in Felhedell.
Localization
The effects of the separation of Aefareth is mainly localised to Northern Aefareth, now known as Felhedell or the Northern Lands. The inhabitants of Southern Aefareth, known as Northumbria, remained largely unaware of the disaster that happened in Felhedell, and were unaware that it was an inhabitated land to begin with.
Those living in Northumbria were told that Felhedell had always been an inhabitable and dangerous land, and that no person nor creature could survive there beside the monsters that infested the lands and craved blood. This was done to make sure that the Northumbria kingdoms wouldn't attempt to reach out to the Felhedell kingdoms, out of the elves' fear that the spirits of the earth would retaliate against Northumbria as well.