J.R.R. Tolkien’s The History of Middle-earth consists of twelve volumes.
Christopher Tolkien edited and published the twelve-volume series between 1983 and 1996. It presents drafts, revisions, notes, and commentary tracing the development of his father’s mythology from early versions to writings connected with The Lord of the Rings and later ideas.
The series is not a single conventional narrative. Its volumes show how names, characters, geography, languages, and plot events changed over decades. Some texts are unfinished or contradictory, so readers use the collection to study Tolkien’s creative process rather than to find one definitive version of every legend.
The series is distinct from The Silmarillion, which Christopher Tolkien edited into a coherent posthumous publication in 1977. It is also separate from Unfinished Tales, published in 1980. Those works contain related material, but neither changes the total of twelve volumes in The History of Middle-earth.