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).
Roy Campbell (poet)
Tolkien, who was then hard at work writing "The Lord of the Rings", was charmed by Campbell. In a letter to his son Christopher, Tolkien compared Campbell to Trotter, a torture-crippled hobbit character who appeared in an early draft of "The Lord of the Rings", to become the character of Aragorn in the final versions. Tolkien further commented, Here is a scion of an Ulster prot. family resident in S. Africa, most of whom fought in both wars, who became a Catholic after sheltering the Carmelite fathers in Barcelona — in vain, they were caught & butchered, and R.C. nearly lost his life. But he got the Carmelite archives from the burning library and took them through the Red country. [...] However it is not possible to convey an impression of such a rare character, both a soldier and a poet, and a Christian convert. How unlike the Left – the 'corduroy panzers' who fled to America [...]