Which Tolkien work contains the creation account called the Ainulindalë?

The creation account called the Ainulindalë appears in J.R.R. Tolkien’s The Silmarillion.

Ainulindalë means “The Music of the Ainur” and forms the opening section of The Silmarillion. It describes how Eru Ilúvatar creates the Ainur and gives them a great musical theme. Their music becomes the imaginative foundation for the creation and history of Eä, the world in which Arda and Middle-earth exist.

The account introduces major ideas that recur throughout Tolkien’s mythology: creation through music, the limits of rebellion, the relationship between divine intention and freedom, and the shaping of history through successive ages. Melkor’s discord is central to the narrative, but the story presents his disruption within a larger design.

Ainulindalë is sometimes treated as though it were a separate novel or an episode from The Lord of the Rings. It is neither. It is the first part of The Silmarillion, followed by Valaquenta and the long histories of the Quenta Silmarillion. Its creation-story structure also distinguishes it from the quest narrative of The Hobbit.