[6] Tolkien was constantly revising his First Age stories; however, the narrative he wrote in 1917, published posthumously in The Book of Lost Tales, remains the only full account of the fall of the city.

Christopher Tolkien retitled the story before including it in Unfinished Tales, because it ends at the point of Tuor's arrival in Gondolin, and does not depict the actual Fall.

"[9] Kane adds that although the book collects material already published, "it still succeeds in rounding out that task", for instance by putting the "Sketch of the Mythology" in the prologue.

Kane admires Alan Lee's illustrations, both in colour and in black and white, as providing "a perfect complement" to the final book in the "unique and remarkable" collaboration between Christopher Tolkien and his father.

"[10] As Tolkien's first tale and the last one to be published by his son, the book is "laden with the sense of weight such a publication brings", taking the reader back to the place where the whole Legendarium began, the story about Eärendel (later called Eärendil).

[10] According to Entertainment Weekly, "Patient and dedicated readers will find among the references to other books and their many footnotes and appendices a poignant sense of completion and finality to the life's pursuit of a father and son.