What is the name of the creator of the universe in J.R.R. Tolkien’s legendarium?

Eru Ilúvatar is the creator of the universe in J.R.R. Tolkien’s legendarium.

In Tolkien’s mythology, Eru is the supreme being and the source of all existence. He creates the Ainur, powerful spiritual beings who participate in the Great Music before the creation of the physical world, Arda.

The Ainur’s music expresses different themes, including the rebellious music of Melkor. Eru then brings the music into reality, creating Eä, the universe in which Arda and Middle-earth exist.

Eru is also called the One. He is distinct from the Valar, who are powerful beings within the created world rather than its ultimate creator. Manwë, Varda, Aulë, and the other Valar serve as governing powers of Arda.

Readers sometimes confuse Eru with Melkor because both are central to the creation story. Melkor is the greatest of the Ainur but is a created being, not the source of creation itself.