"On my father's death it fell to me to try to bring the work into publishable form. It became clear to me that to attempt to present, within the covers of a single book, the diversity of the materials -- to show The Silmarillion as in truth a continuing and evolving creation extending over more than half a century -- would in fact lead to confusion and the submerging of what is essential.
-Christopher Tolkien, from the Foreword
Upon occasion, a scholar finds that the organization and presentation of another person's life work becoming his or her own life's work, and a fulfilling one at that. After the death of J.R.R. Tolkien in 1973, his son Christopher Tolkien was left with a collection of fragmentary stories and notes about the mythology underyling The Hobbit and The Lord of the Rings. Since this mythology was built up over its creator's entire lifetime, built like a painting in layers which were often covered up by later layers, the task was certainly daunting. But the younger Tolkien, with the assistance of Guy Gavriel Kay, began to go through his father's half-finished manuscripts, notes, and scribblings, to put something together that could be presented to the world. The Silmarillion, published in 1977, was the admirable result.
* * * * *
What resulted was less a novel and more of a series of related stories in the tradition of Norse sagas:
Ainulindalë is the theology behind the creation of Arda, the pattern set by the Ainur and its realization by Ilúvatar; Valaquenta is a list of the Ainur who entered Arda, the Powers of the Earth, or Valar.
The central work, Quenta Silmarillion, is itself more a collection of sagas than a single narrative. It begins as an æteological work, telling of how the works and struggles of the Valar shaped Arda, and continues with the appearance of the Eldar and their journey to Valinor. It then moves into the story of Fëanor and the Silmarils, their theft by Melkor, the revolt of the Noldor, and their return to Middle-Earth.
After a while, however, the thread of the narrative becomes frayed. As the relative peace of Beleriand is smashed by Morgoth, so too is the tale, and we must follow it in a patchwork fashion across several stories, the Lay of Leithian about tale of Lúthien and Beren, the Narn I Hîn Húrin, about Túrin Turambar, and finally, the story of Eärendil.
The last two sections connect the events of the First Age to the time of the Lord of the Rings along two parallel tracks. All of the information in Of the Rings of Power and the Third Age will be recognizable if you have read LotR carefully enough.
Tolkien brings the story full circle by telling us his source: Bilbo Baggins's Translations from the Elvish contained within the Red Book of the Westmarch, handed down through history.
The Silmarillion's fragmentary nature is a strength rather than a drawback. It works to convince us that this is a real mythology built from stories collected over millennia rather than something made up on the spot for money. After all, this is exactly what it is!
After the release of The Silmarillion, Christopher Tolkien embarked upon the presentation of the rest of his father's notes, possible other ways he might have put the story together. The publisher, Houghton Mifflin, has packaged as these as "The History of Middle-Earth", containing early versions of the mythology abandoned by the elder Tolkien, as well as buried layers of the story. While interesting in their own right, these latter works frequently come off as broad brush strokes better left covered by the artist. Regardless of individual merit, however, all of them draw their strength from the Silmarillion and you will always find youself comparing them to it. If nothing else, they show the excellent work done by Kay and the younger Tolkien, showing that he really made the best choices while pulling together the original publication.