Elwin Ransom
Elwin Ransom may be based on C. S. Lewis' friend J. R. R. Tolkien ("Elwin" means "Elf friend" in Anglo-Saxon), though he seems to have autobiographical elements. In "That Hideous Strength" Ransom, with his royal charisma and matter-of-fact breezy acceptance of the supernatural, appears less like Tolkien than like Charles Williams (or some of the heroes in Williams' books).
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.