The Lord of the Rings is an epic high fantasy novel written by English philologist and University of Oxford professor J.R.R. Tolkien. The story began as a sequel to Tolkien's earlier, less complex children's fantasy novel The Hobbit (1937), but eventually developed into a much larger work. It was written in stages between 1937 and 1949, much of it during World War II. It is the third best-selling novel ever written, with over 150 million copies sold.

The title of the novel refers to the story's main antagonist, the Dark Lord Sauron, who had in an earlier age created the One Ring to rule the other Rings of Power as the ultimate weapon in his campaign to conquer and rule all of Middle-earth. From quiet beginnings in the Shire, a Hobbit land not unlike the English countryside, the story ranges across north-west Middle-earth, following the course of the War of the Ring through the eyes of its characters, notably the hobbits Frodo Baggins, Samwise "Sam" Gamgee, Meriadoc "Merry" Brandybuck and Peregrin "Pippin" Took, but also the hobbits' chief allies and travelling companions: Aragorn, a Human Ranger; Boromir, a man from Gondor; Gimli, a Dwarf warrior; Legolas, an Elven prince; and Gandalf, a Wizard.