J. R. R. Tolkien
The request for a sequel prompted Tolkien to begin what would become his most famous work: the epic novel "The Lord of the Rings" (originally published in three volumes 1954–1955). Tolkien spent more than ten years writing the primary narrative and appendices for "The Lord of the Rings", during which time he received the constant support of the Inklings, in particular his closest friend C. S. Lewis, the author of "The Chronicles of Narnia". Both "The Hobbit" and "The Lord of the Rings" are set against the background of "The Silmarillion", but in a time long after it.
P. R. Stephensen
Stephensen was a prolific author. He published over 30 books, as well as translations of works by Vladimir Lenin and Friedrich Nietzsche. He also produced nearly 70 books ghostwritten for historian Frank Clune. He was a friend of D. H. Lawrence and edited the first uncensored version of "Lady Chatterley's Lover". He was also friends with author Aldous Huxley.