Tolkien began writing The Lord of the Rings in 1937, starting work on what he initially called “a new Hobbit” after The Hobbit became a publishing success. His publisher, George Allen & Unwin, wanted another book about hobbits, and Tolkien began the opening chapter in December of that year.
In a letter dated 19 December 1937, Tolkien reported that he had written the first chapter, “A Long-Expected Party.” At that stage, he had not yet settled on the Ring-centered epic or the darker mythology that would define the finished novel. The project gradually expanded far beyond a children’s sequel.
Writing was repeatedly interrupted by Tolkien’s academic work, teaching, marking, and the disruptions of the Second World War. He also made many false starts and revised the characters, chronology, languages, and larger history as the manuscript developed.
The work took more than a decade to complete. The three volumes were published in 1954 and 1955: The Fellowship of the Ring, The Two Towers, and The Return of the King. Thus, 1937 marks the beginning of composition, not publication.