Legend of the Abyss
In the time only remembered, the elven empire of Aelrretyn stretched across all that was known. Eventually the Elves, in their vanity, sought to become as powerful as The Old Ones who had given them life. The war now known only as Maique ended with the destruction of the Old Ones. Victorious against the most powerful gods, the elves rejoiced in their new gory, only to find that the power they had harnessed to defeat the Old Ones began to destroy their new world. As it crumbled around them, the god Ásvaldr, one of the lesser god’s created by the Old Ones, saw the chaos and destruction that the elven kingdom had wrought and halted it. Then he separated the weakened elves from their Arcane inheritance, and gave it to the lesser race of Humans. This was the Tearing.
The remains of the world became raging seas and stone, the surface was a place inhospitable to the living, and the races sought refuge in the shattered and cracked depths of the Terra. The crust, however, was not empty. Long had the Dwarfs built their kingdom in the depths, and now the empire they had been forced to pay fealty to was seeking refuge in their halls. The Dwarf rulers refused to admit the elves into their lands, hence leaving them to claw for life on the surface. To the humans, however, they allotted their own cities in exchange for use of their new found Arcane abilities, in their kingdom, and their constant war ageist the Orcs of the Svartalfheim.
And so the world of known as Abyss in the human tongue came to be known as it is today.