Arien was originally a Maia of Vána the Ever-young, though in some writings she served Varda. She was "from the beginning a spirit of fire" and never listened to Melkor in the least. Her eyes were too bright even for the elves to look at, and Melkor's servants were terrified of her. While in Valinor she took a form similar to that of the Valar, but when she left she was a "naked flame of fire, burning in the fullness of her splendour." Arien was more powerful than Tilion, the guardian of the Moon. However, when the Two Trees of Valinor were destroyed, Arien took the last surviving fruit of Laurelin, the golden tree of the Valar, in a vessel forged by Aulë and carried it away in the Heavens. As Arien is the guardian of the Sun, she is one of the most loved Maiar by mortal men, and her first journey across the sky was the signal of their awakening.
Urien and Urwendi are the earlier names for Arien, which both mean "Maiden of Fire".
Other versions of the legendarium
In other writings, Morgoth wanted to claim Arien as a wife, and ravished her, upon which she abandoned her body and "died", leaving the Sun to travel through the skies uncontrollably and burning parts of Arda.
- The Silmarillion, Quenta Silmarillion, Chapter XI: "Of the Sun and Moon and the Hiding of Valinor"
- The Silmarillion, Appendix: Elements in Quenya and Sindarin names
- The History of Middle-earth, Vol. 1: The Book of Lost Tales Part One, Appendix: Names in the Lost Tales – Part I
- The History of Middle-earth, Vol. 1: The Book of Lost Tales Part One, IX: "The Hiding of Valinor"