Beleriand

At the end of the First Age of Middle-earth Y.S. 583, Beleriand was broken in the War of Wrath by the angelic beings, the Valar against the demonic Morgoth (himself a Vala fallen into evil). As the inhabitants of Beleriand, including masterless Orcs, beasts of Angband, Elves, Men and Dwarves, fled, much of Beleriand sank in the sea. Only a small section of East Beleriand remained, and was known after as Lindon, in the Northwest of Middle-earth of the Second and Third Age. Other parts of East Beleriand survived into the Second Age, but were completely destroyed along with the island kingdom of Númenor. [1]