The Silvan elves were notably of Nandorin background who descended from the followers of Lenwë who were fascinated by the landscape and its features of the lands East of the Misty Mountains, and followed the Great River down into south and beyond. Many centuries later, they reappeared and spread themselves throughout the regions between the Misty Mountains and the Blue Mountains. Later, they appeared in the Beleriand under the leadership of their only king Denethor and were allied to Thingol, the King of Doriath. When Morgoth attacked the Beleriand, Denethor was killed and his people suffered heavy causalities and later became a secretive people throughout the rest of the First Age.
When the Beleriand was lost, the Silvan elves who survived rejoined their kindred east of the Misty Mountains and over the ages gradually became citizens of the Elven realms of Lórien and Greenwood the Great or later Northern Mirkwood, or were at times wanderers.