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).
Edward Tangye Lean
After leaving Leighton Park School, Tangye Lean was an undergraduate at University College, Oxford. While at Oxford, he founded the original Inklings club around 1931, for the reading of unfinished compositions. The club consisted of students and dons, including J. R. R. Tolkien and C. S. Lewis. When Lean left Oxford in 1933, the club faltered. However, its name was transferred by Tolkien and Lewis to their literary group at Magdalen College. Lean also contributed to the "Isis" magazine at Oxford.