What was J.R.R. Tolkien’s final completed Middle-earth novel published during his lifetime?

The Lord of the Rings was J.R.R. Tolkien’s final completed Middle-earth novel published during his lifetime.

The work appeared in three volumes from 1954 to 1955: The Fellowship of the Ring, The Two Towers, and The Return of the King. It follows the quest to destroy the One Ring and expands the history, geography, languages, and peoples first introduced to a wide readership in The Hobbit.

Tolkien continued developing Middle-earth material after completing The Lord of the Rings, especially the legends later associated with The Silmarillion. However, The Silmarillion was unfinished at his death and was edited and published posthumously by his son Christopher Tolkien in 1977. Unfinished Tales was also published after Tolkien’s death and is a collection rather than a completed novel.

The phrase “published during his lifetime” matters because Tolkien’s posthumously edited books contain substantial Middle-earth material but were not final published novels completed and released by Tolkien himself. The Lord of the Rings remains his last major completed Middle-earth narrative issued while he was alive.