Númenor , also called Elenna-nórë or Westernesse, is a fictional place in J. R. R. Tolkien's writings. It was a huge island located in the Sundering Seas to the west of Middle-earth, the main setting of Tolkien's writings, and was known to be the greatest realm of Men. However, the inhabitants' cessation of the service to Eru Ilúvatar and rebellion against the Valar led to the downfall of the island and death of the majority of its population.