The forerunner to The Lord of the Rings, The Silmarillion fills in the background which lies behind the more popular work, and gives the earlier history of Middle-earth, introducing some of the key characters.
The tales of The Silmarillion are set in an age when Morgoth, the first Dark Lord, dwelt in Middle-Earth, and the High Elves made war upon him for the recovery of the Silmarils, the jewels containing the pure light of Valinor.

Included on the recording are several shorter works. The Ainulindale is a myth of the Creation and in the Valaquenta the nature and powers of each of the gods is described. The Akallabeth recounts the downfall of the great island kingdom of Numenor at the end of the Second Age and Of the Rings of Power tells of the great events at the end of the Third Age, as narrated in The Lord of the Rings.