Middle-earth canon

Although Tolkien said that The Hobbit was conceived separately from his mythological stories,[7] early drafts show that it was set in that world, referring explicitly to characters and places which appeared in his Book of Lost Tales which would later become The Silmarillion.

The Necromancer was originally Thû, the precursor of Sauron; Thorin's grandfather was imprisoned in the same dungeons that held Beren and Lúthien; the Elven king was Thingol and his land Menegroth.

This reframing made some details in The Hobbit, such as the goblins' ready recognition of the ancient swords Orcrist and Glamdring, difficult to reconcile into a single history.

"[12]Throughout his commentaries in Unfinished Tales and the twelve volumes of The History of Middle-earth, Christopher Tolkien points out differences between various versions of the original texts and the final editorial selections and occasional alterations in The Silmarillion.

In the Introduction of Unfinished Tales he observes that such selection was necessary to publishing a unified narrative;[13] in some cases he later came to feel that he went too far, most particularly in creating a synthesis of original material and existing texts for the chapter on the ruin of Doriath in The Silmarillion, where his father's pre- and post-Lord of the Rings writings were apparently irreconcilable: "I think now that this was a mistaken view, and that the undoubted difficulties could have been and should have been, surmounted without so far overstepping the bounds of editorial function.

For example: From The Silmarillion: "In the front of that fire came Glaurung the golden, father of dragons, in his full might; and in his train were Balrogs, and behind them came the black armies of the Orcs in multitudes such as the Noldor had never before seen or imagined."

— p. 151.From The Lost Road: "In the front of that fire came Glómund the golden, the father of dragons, and in his train were Balrogs, and behind them came the black armies of the Orcs in multitudes such as the Gnomes had never before seen or imagined."

— p. 280.In the continuing development of the published history of Middle-earth, Christopher Tolkien quotes in The Children of Húrin his father's own words on his fictional universe: "once upon a time...

"[15]Christopher Tolkien offers this justification for exercising his editorial authority to produce The Children of Húrin as a separate book: "...it has seemed to me that there was a good case for presenting my father's long version of the legend of the Children of Húrin as an independent work, between its own covers, with a minimum of editorial presence, and above all in continuous narrative without gaps or interruptions, if this could be done without distortion or invention, despite the unfinished state in which he left parts of it.

"[16] Ethan Gilsdorf reviewing The Children of Húrin wrote of the editorial function: "Of almost equal interest is Christopher Tolkien's task editing his father's abandoned projects.

Its creator developed various elements of his fiction over the course of decades, making substantial changes including the abandonment of major themes, facts and entire tales, and undertook wholesale rewrites and revisions of otherwise "complete" narratives.

[The Lord of the Rings] is, I think, due to the glimpses of a large history in the background: an attraction like that of viewing far off an unvisited island, or seeing the towers of a distant city gleaming in a sunlit mist.