Using the light of the Silmaril to guide them through the Enchanted Isles, Eärendil and Elwing successfully reached Valinor. Eärendil pleaded before the Valar for mercy and aid on behalf of Elves and Men. Moved by his selfless plea, the Valar launched the War of Wrath, utterly destroying Angband and casting Morgoth into the Void. The Valar set Eärendil’s ship into the heavens, with the Silmaril bound to his brow. It became the Star of Eärendil, a beacon of hope for all of Middle-earth.
In the Noontide of Valinor, before the Sun and Moon existed, the world was illuminated by the golden and silver light of the Two Trees, Laurelin and Telperion. It was in this era that Fëanor, the greatest of the Elven smiths and the most brilliant and haughty of the Noldor, conceived his masterpiece.
The Silmarils symbolize not only the artistic and creative genius of the Elves but also the themes of loss, rebellion, and the unyielding pursuit of justice and beauty. They are central to Tolkien's exploration of the nature of evil, the importance of light in the face of darkness, and the complex interplay between fate and the actions of individuals.
When the Varda, the Queen of the Valar, saw the Silmarils, she hallowed them. Thereafter, no mortal flesh, nor anything unclean or evil, could touch them without being scorched and withered by their pure sanctity. The Great Theft and the Oath of Fëanor
In Tolkien's legendarium, the Silmarils are the "pièce de résistance" of all Elvendom, driving the history of the First Age.