Middle-earth legendarium

Tolkien's legendarium is the term for the entirety of J. R. R. Tolkien's mythopoetic writing that forms the background to his The Lord of the Rings. Tolkien worked and re-worked the components of his legendarium throughout his adult life, or during a period of more than 50 years; the earliest drafts, published in The Book of Lost Tales (1983) dating to 1916.

Colloquially, "Middle-earth" is popularly used as a shorthand for a "canonical" or mature form of Tolkien's narrative, Middle-earth being Tolkien's term for the inhabited part of the world in which most of his published stories were set.

The mythological and cosmological background of Tolkien's published works was sketched in the posthumously-published The Silmarillion (1977), and in Tolkien studies as a field as it has developed since the 1980s.

The term legendarium refers to a literary collection of legends. This medieval Latin noun originally referred mainly to texts detailing legends of the lives of saints. A surviving example is the Anjou Legendarium, dating from the 14th century. Quotations in the Oxford English Dictionary for the synonymous noun legendary date from 1513. The Middle English South English Legendary is an example of this form of the noun.

Tolkien used the term legendarium with reference to his works in a total of four letters he wrote between 1951 and 1955, a period in which he was attempting to have his unfinished Silmarillion published alongside the more complete The Lord of the Rings:

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