What was the title of Tolkien’s unfinished mythology later published as The Silmarillion?

The Silmarillion is the title of the mythology Tolkien developed throughout his life and that was published after his death. It was edited and arranged by his son Christopher Tolkien and released in 1977.

Unlike The Hobbit or The Lord of the Rings, The Silmarillion is not a single adventure centered on one protagonist. It contains creation stories, accounts of the divine Valar, the history of the Elves, and narratives about the First Age of Middle-earth, including the wars against Morgoth.

Tolkien repeatedly revised the material and did not complete a definitive final form before his death in 1973. Christopher Tolkien therefore selected and organized writings from different periods. The published book’s title is linked to the Silmarils, three jewels created by Fëanor and central to many of its major stories.