Unfinished Tales (full title Unfinished Tales of Númenor and Middle-earth) is a collection of stories and essays by J. R. R. Tolkien that were never completed during his lifetime, but were edited by his son Christopher Tolkien and published in 1980.
Unlike The Silmarillion, for which the narrative fragments were modified to connect into a consistent and coherent work, the Unfinished Tales are presented as Tolkien left them, with little more than names changed (the author having had a confusing habit of trying out different names for a character while writing a draft). Thus some of these are incomplete stories, while others are collections of information about Middle-earth. Each tale is followed by a long series of notes explaining inconsistencies and obscure points.
As with The Silmarillion, Christopher Tolkien edited and published Unfinished Tales before he had finished his study of the materials in his father's archive. Unfinished Tales provides more detailed information about characters, events and places mentioned only briefly in The Lord of the Rings. Versions of such tales including the origins of Gandalf and the other Istari (Wizards), the death of Isildur and the loss of the One Ring in the Gladden Fields, and the founding of the kingdom of Rohan help expand knowledge about Middle-earth.
The commercial success of Unfinished Tales demonstrated that the demand for Tolkien's stories several years after his death was not only still present, it was growing. Encouraged by the result, Christopher Tolkien began to embark upon the more ambitious twelve-volume work entitled The History of Middle-earth which encompasses nearly the entire corpus of Tolkien's writings about Middle-earth.
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