It is well established that Morgoth forced the Incomers to dwell in Hithlum after the Nirnaeth of I 472. It is rather less well established how long they held that land. In I 545 the forces of the Valar landed in Beleriand to challenge Morgoth and the War of Wrath began. It hardly seems credible that those forces would have tolerated a nearby land occupied by enemies as they marched against Angband. At some point, then, the Incomers would presumably have been defeated or driven out by the armies of the West. We have no details of such a conflict, but it nonetheless seems safe to assume that the Incomers would have held Hithlum for no more than a century at the most. By the end of the War of Wrath (I 587), the lands of Hithlum and Dor-lómin were drowned beneath the Great Sea.