Arda is Tolkien's version of Earth, with Middle-Earth being its main continent where LOTR stories unfold. Arda changed over ...

Eru Ilúvatar is the supreme being that created Arda and everything within it ... In this way, there is really only one God of Middle-earth, as all the other created beings (who could be ...

His mystery posits him as a possible rival to Manwë's claim of the second-most powerful being in all of Arda, but regardless, he didn't create Middle-earth from its foundations like Manwë.