A half-elf, known today mainly through J. R. R. Tolkien's Middle-earth writings but with origins in Norse mythology, is the offspring, possibly very beautiful and with magical powers, of an elf and a human. In Middle-earth, half-elves are the children of Elves and Men, and can choose either Elvish immortality or the mortal life of Men. The elf-maidens Lúthien and Arwen both chose mortality.