Eru Ilúvatar is the creator deity in J.R.R. Tolkien’s mythology. He is the supreme being who creates the Ainur and brings the world of Eä into existence.
In the Ainulindalë, the opening section of The Silmarillion, Ilúvatar gives the Ainur themes of music. Their performance becomes a vision of the history of the world, and Ilúvatar then gives that vision independent reality. The account establishes creation through music, a recurring idea in Tolkien’s mythology.
Ilúvatar is also called the One. The Valar and Maiar are powerful spiritual beings created by him, but they are not equal to him. Melkor, later known as Morgoth, rebels against the intended harmony, while the other Ainur help shape and govern the world.
Readers sometimes identify Manwë or Melkor as the supreme figure because both are prominent in the early mythology. Manwë is the chief of the Valar, and Melkor is the greatest rebel, but Eru Ilúvatar occupies the unique creator role.