Númenor was J.R.R. Tolkien’s fictional island civilization in the Second Age.
The island kingdom was granted to the Men who had helped the Elves and the Valar during the First Age. Its inhabitants, the Númenóreans, enjoyed long lives and became powerful mariners. Over time, however, pride, fear of death, and hostility toward the Valar transformed the kingdom’s history.
Númenor was destroyed in a cataclysm during the Second Age after its king, Ar-Pharazôn, led an invasion connected with the desire for immortality. The survivors included Elendil and his sons, who founded the realms of Arnor and Gondor in Middle-earth.
Númenor is sometimes confused with Valinor, the blessed realm across the sea, or Beleriand, a region destroyed at the end of the First Age. Its story also echoes Tolkien’s interest in Atlantis traditions, though Númenor has its own detailed mythology and chronology.