Aredhel was the daughter of Fingolfin, younger than her brothers Fingon and Turgon. Like them, she was caught in the Oath of Feanor. She crossed the Helcaraxe with Fingolfin's host in pursuit of Feanor and a new life in Middle-earth. She was tall, strong, and dark-haired. She was called Ar-Feiniel, the White Lady of the Noldor, for her habit of dressing in silver and white. She was often in the company of her kin, the sons of Feanor, but did not give any of them her heart.
She later married Eol for convenience, and their son was Maeglin. She had left her brother, Turgon's, city of Gondolin to visit the sons of Feanor and became separated from her escort by the creatures of Ungoliant in hostile and unknown territory, as she was not allowed to pass into the safety of the "Girdle of Melian". The escort believed her dead, but she managed to find her way to the lands of Celegorm. But as he did not return that year, she became restless and became lost in the forest of Nan Elmoth, darkest and tallest of trees in Beleriand where the sun never came. Eol lived there, and gave her a place of haven, and married her. She was allowed to wander to her heart's content, except to see any of the Noldor elves, for whom Eol held to blame for the return of Morgoth. Maeglin grew up and loved to hear tales of Turgon and his daughter, and it reminded Aredhel that she would like to return there. Eol would not allow it. The two slipped away while he was gone, pursued after two days by Eol. Eol found them at last, but Turgon would not force the pair to leave with Eol. Also, Eol could not leave with the secret location, and he and his son would have to abide or die. Aredhel guessed Eol's mind and jumped in front of Maeglin, so that Eol's javelin hit her instead of her son. It seemed no mortal wound, but it had been poisoned and she died. Eol was cast from the walls of the city, but first he cursed Maeglin to fail of all his hopes and die the same way as Eol.
Maeglin could not marry Idril, Turgon's daughter, as they were too close kin. Instead her heart went to the human emissary of Ulmo, Tuor, and Maeglin felt hatred for him, and tried to hide both feelings. He had to watch them be happy and have their son, Earendil.
Morgoth captured and tortured Maeglin into giving him information on how to enter and assail Gondolin, the hidden city of Turgon. Maeglin's hatred made him agree to betray the city from within. Maeglin tried to steal Idril and seven-year old Earendil from the city as it was being destroyed, but Tuor caught him and pitched him over the wall. Thus was Eol's curse finished.