Before The Silmarillion, The Hobbit and The Lord of the Rings, the earliest myths and legends of Middle-earth and Valinor were laid down in The Book of Lost Tales, written by J.R.R. Tolkien between 1916 and 1920, and compiled by Christopher Tolkien for publication in 1983.

This second part of The Book of Lost Tales includes the tale of Beren and Lúthien, Túrin and the Dragon, and the only full narratives of the Necklace of the Dwarves and the Fall of Gondolin, itself the finest and most exciting depiction of a battle that Tolkien ever wrote. Each tale is followed by a commentary in the form of a short essay, together with texts of associated poems, and contains extensive information on names and vocabulary in the earliest Elvish languages.