The three Silmarils were jewels created by Fëanor, most gifted of the Elves. Within them was imprisoned the Light of the Two Trees of Valinor before the Trees themselves were destroyed by Morgoth, the first Dark Lord.
Thereafter, the unsullied Light of Valinor lived on only in the Silmarils, but they were seized by Morgoth and set in his crown, which was guarded in the impenetrable fortress of Angband in the north of Middle-earth.
