Quote Originally Posted by Pannonian View Post
"The Lord of the Rings is of course a fundamentally religious and Catholic work; unconsciously so at first, but consciously in the revision. That is why I have not put in, or have cut out, practically all references to anything like 'religion', to cults or practices, in the imaginary world. For the religious element is absorbed into the story and the symbolism."

No. 142: letter to his friend Robert Murray, S.J. (December 1953)
I don't see how being Catholic cancels being Christian. And if we zoom out of LoTR and look at the whole legendarium we see that it establishes its own universe whose origin is definitely at variance with the Christian tradition starting from its creation out of Music. The religious background of the legendarium is richer than just Catholicism or even Christianity with the admixture of Scandinavian and even Greek mythology.