J.R.R. Tolkien was not only an amazing writer but an avid linguist and he developed several languages for his books which include The Hobbit and The Lord of the Rings series. I think that if anyone deserves to have their fantasy languages on Duolingo it is J.R.R. Tolkien. He did a very thorough job and he is certainly qualified, being a linguist and all. I would definitely learn his languages. What do you all think?
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To answer the question what I think -
My understanding of the relationship between the books and the languages is backwards to what your synopsis reflects; Tolkeinn did not create languages for his books. He created books for his languages. The evolution of the languages was, from my understanding, the first aspect of Middle Earth that Tolkeinn developed and filled in backstory for the changing cultures to that spoke these changing languages and from that story came the Hobbit books.