I am almost done with “The Return of the King” during my slow-read of all of Tolkien’s Middle Earth works.
There seems to be a lot of Catholic imagery in the LOTR trilogy-proper: Lembas, Galadriel, The One Ring as sin itself.
Here is someone reciting a decade of the Rosary in “Elvish”. This is not fan fiction: Tolkien himself translated these specific prayers in letters to his son Christopher. The person praying is just reading Tolkien’s actual words.