Originally conceived quite independently of the vast cycle of legends on which Tolkien had already been working for some fifteen years, The Hobbit, or There and Back Again, a children's story, is the work in which elements of these legends are, for the first time, glimpsed within a more or less novelistic narrative. It was not the first story told to Tolkien's own children that achieved written form (Roverandom, published posthumously, preceded it), but it is the longest and most effective. Partially drafted around 1931-32, it attracted the attention of the publishers Allen & Unwin and was completed in 1936. Its success on publication in 1937 motivated the composition of The Lord of the Rings which is its sequel …
Rosebury, Brian. "The Hobbit". The Literary Encyclopedia. First published 08 March 2001; last revised 30 November -1.
[http://www.litencyc.com/php/sworks.php?rec=true&UID=586, accessed 18 April 2015.]