Elves of Sirion
From Tolkien Gateway
The Elves of Sirion were members of a short-lived Elven culture that grew up in the lands around the Mouths of Sirion during the last years of the First Age. They were mainly Elves that had fled from the destruction of the great realms of Beleriand, especially Gondolin and Doriath. Many of these Elves were killed, not by the Dark Lord Morgoth, but by the remaining Sons of Fëanor who sought the Silmaril of Elwing, who dwelt with the Elves of Sirion.