The Dagor-nuin-Giliath, or Battle under Stars, was the Second Battle of the Wars of Beleriand and the first battle involving the Noldor. It was fought between the followers of Fëanor and Morgoth’s armies during the Noldor’s first days in Middle-earth, and began when the Noldor arrived unexpectedly at the Firth of Drengist and passed through the Gate of the Noldor into Hithlum. As it was fought so soon after Fëanor’s return that the Moon had not risen for the first time yet, it became known as the Battle Under Stars.
Morgoth hoped to destroy the Noldor before they could establish themselves, so he sent an army of Orcs to launch a surprise attack on the Noldor. Although the Orcs outnumbered the Elves, the Noldor were empowered by the Light of Valinor, and quickly defeated their enemies; many Orcs fled back over the Mountains, where they joined with their reinforcements. They were chased across the Ard-galen and into the Fen of Serech, by Celegorm, and there they were destroyed.
The forces of Morgoth that had been besieging the Havens of the Falas since the First Battle of Beleriand marched north to attack the Noldor from the rear, but Celegorm and his forces ambushed them at Eithel Siririon, trapping the Orcs between the two Noldorin forces. For ten days they fought continuously. All but a few Orcs perished, and Fëanor pursued even the few survivors. Fëanor went on towards Angband in the hopes of defeating Morgoth and retrieving the Silmarils. With just a few soldiers, he left his armies behind. At the edge of Dor Daedeloth, they were attacked by Balrogs set loose from Thangorodrim, and though Fëanor stood his ground, he was fatally wounded. He died just before Angband, thrice cursing Morgoth. The armies of his sons soon reached him, and the Orcs and Balrogs retreated.
The Moon rose, and with it, Fingolfin and the second and greater Host of the Noldor arrived in Lammoth, where they were attacked by Orcs sent there by Morgoth. Here they fought their first battle, the Battle of Lammoth. The Noldor were caught off guard, and Argon, son of Fingolfin, was slain. Fingolfin and his host pursued the Orcs until they were all destroyed, and as the Sun first rose they passed into Mithrim.