According to the fictional history in The Silmarillion, the evil Vala Melkor corrupted lesser Maiar (angelic beings) to his service in the days of his splendour before the making of Arda. Upon the awakening of the Elves, the Valar captured Melkor and destroyed his fortresses Utumno and Angband. But they overlooked the deepest pits, where, with many of Melkor's other allies, the Balrogs fled into hiding. When Melkor returned to Middle-earth from Valinor, now bearing the epithet Morgoth, he was attacked by the evil giant spider Ungoliant; his scream drew the Balrogs out of hiding to his rescue.