Cover illustration by John Howe

A combined index named The History of Middle-earth: Index (ISBN 0007137435) was compiled by Helen Armstrong from the indices of the twelve original volumes. It was published in 2002 by HarperCollins in paperback, six years after the series by Christopher Tolkien was completed, and then again in 2010.

The book creates a supreme index charting the writing of The Lord of the Rings and The Silmarillion. It also complements the History of Middle-earth  series, repackaged to complement the distinctive and classic style of the '"black cover" A-format paperbacks of The Hobbit, The Lord of the Rings, The Silmarillion, and Unfinished Tales.

It is 484 pages long, and is designated as the thirteenth (and last) volume of The History of Middle-earth.

The History of Middle-earth Series (1983 - 2002)

The Book of Lost Tales Part One | The Book of Lost Tales Part Two | The Lays of Beleriand | The Shaping of Middle-earth | The Lost Road and Other Writings | The Return of the Shadow | The Treason of Isengard | The War of the Ring | Sauron Defeated | Morgoth's Ring | The War of the Jewels | The Peoples of Middle-earth | The History of Middle-earth: Index