It is no exaggeration to say that much more of J.R.R. Tolkien's work has appeared since his death than was ever published while he was alive. After the publication of Unfinished Tales of Númenor and Middle-earth in 1980 — itself the third posthumous collection of Tolkien's writings to reach the public — his son and literary executor, Christopher Tolkien, proposed “an unflinchingly scholarly treatment” (Unwin “Early Days” 5) of the vast amount of unpublished and often unfinished material Tolkien left behind, aimed at guiding “the serious pilgrim […] along all the paths, and variants, and blind ends of his father's creation” (ibid.). This treatment was originally planned for four volumes, but the scope of the …
Fisher, Jason. "The History of Middle-earth". The Literary Encyclopedia. First published 11 February 2010; last revised 30 November -1.
[http://www.litencyc.com/php/sworks.php?rec=true&UID=21928, accessed 28 April 2015.]