Arwen Undómiel is a fictional character in J. R. R. Tolkien's Middle-earth legendarium. She appears in the novel The Lord of the Rings. Arwen is one of the half-elven who lived during the Third Age; her father was Elrond half-elven, lord of the Elvish sanctuary of Rivendell, while her mother was the Elf Celebrian, daughter of the Elf-queen Galadriel, ruler of Lothlórien. She marries the Man Aragorn, who becomes King of Arnor and Gondor.

The Lord of the Rings is an epic high fantasy novel by the English author and scholar J. R. R. Tolkien. Set in Middle-earth, the story began as a sequel to Tolkien's 1937 children's book The Hobbit, but eventually developed into a much larger work. Written in stages between 1937 and 1949, The Lord of the Rings is one of the best-selling books ever written, with over 150 million copies sold.