What is the title of the first volume in J.R.R. Tolkien’s The History of Middle-earth?

The first volume in J.R.R. Tolkien’s The History of Middle-earth is The Book of Lost Tales 1.

Edited by Christopher Tolkien, the twelve-volume History of Middle-earth examines drafts, revisions, notes, and related writings that show how Tolkien’s mythology developed. The first volume, published in 1983, presents the earliest substantial form of that mythology, written mainly between 1917 and the early 1920s.

The Lost Tales are framed as stories told to a human mariner named Eriol, who visits the island of Tol Eressëa. Their versions of the creation of the world, the Valar, the Elves, and the great wars differ considerably from the later published Silmarillion.

The title is sometimes given simply as The Book of Lost Tales, but the volume is formally identified as The Book of Lost Tales 1 because The History of Middle-earth divides the material into two books. The second volume continues the early cycle.