In J.R.R. Tolkien’s mythology, what is the name of the creator of Eä?

Eru Ilúvatar is the creator of Eä in J.R.R. Tolkien’s mythology.

Eru, also called Ilúvatar, first creates the Ainur, powerful spiritual beings who participate in the Great Music. From that music he brings the universe, known as Eä, into existence. The Ainur who enter the world become the Valar and Maiar.

This creation story appears most fully in The Silmarillion, especially in “Ainulindalë,” the account of the Music of the Ainur. Melkor introduces discord into the music, but Ilúvatar incorporates even that rebellion into a larger design.

Manwë is the chief of the Valar, Morgoth is the fallen Vala Melkor, and Aulë is the Vala associated with craftsmanship. None of them is the ultimate creator of Eä.