NEW YORK (CNS) -- The necromancer Sauron, the archvillain of "The Lord of the Rings," makes a cameo appearance in director Dome Karukoski's "Tolkien." He looms over the Battle of the Somme in World War I as if he were at home in his realm of Mordor and the bloody conflict had all been his idea.

It's one of many images designed to make the case that the Great War was the crucible that forged J.R.R. Tolkien's imagination. His experience of the conflict, so the implicit argument goes, compelled him to write "fairy stories," as he called them, about Middle-earth, a pre-Christian land occupied, among others, by Hobbits whose heroism nonetheless emerges, at least in part, from a decidedly Christian morality.

As for the author's Catholic faith, it’s almost entirely absent from the film. Many critics have commented on this.

Armond White, in the National Review, for instance, wrote that Tolkien's "Catholic background ... (is) reduced to a surreal battlefield vision of a crucifix and a passing reference to religious prejudice." Anthony Lane, reviewing for The New Yorker, observed, "The movie, as embarrassed by religion as 'The Lord of the Rings' is by sex, averts its gaze from the Catholic faith by which Tolkien was sustained."

Yet, in fairness, this might be asking too much of this movie, or any movie. Because it was subtle and internal, the faith that inspired Tolkien (1892-1973) would be difficult to capture on screen. Trench warfare, charming tearooms and romantic tension are time-proven tropes and, by comparison, substantially easier to portray.

Much of the story, as written by David Gleeson and Stephen Beresford, focuses on Tolkien's deep attachment to medieval imagery and philology -- the study of language -- from childhood onward to his student days at Oxford University. In connection with "The Lord of the Rings," Tolkien created a family of languages, collectively known as Elvish, at least two of which are fully developed.

The haunting imagery of Tolkien's books gets underlined -- several times -- so audiences won’t miss his supposed sources. Even smoky, noisy Birmingham, England, is a stand-in for Mordor in one sequence.

It's just one way of explaining Tolkien. Since his death -- and, more recently, with the unflagging popularity of his books reinforced by a series of hit films -- a considerable industry of academic scholarship has been devoted to debating the meaning of his work. These studies, too, only occasionally delve into the author's Catholicism.

The man himself, who called his work, in one letter, "fundamentally religious and Catholic," was reluctant to make explicit connections. In another letter he wrote, "But only one's guardian angel, or indeed God himself, could unravel the real relationship between personal facts and an author's works."

His first biographer, Humphrey Carpenter, warned: "No account of the external events of Tolkien's life can provide more than a superficial explanation of his mythology."

So perhaps it’s best not to try to explain the origins of Bilbo Baggins and his pals, and not to theorize, as some have done, that Frodo, for example, represents Jesus Christ, Samwise Gamgee St. John the Evangelist and Gandalf the angel who rescued St. Peter. Middle-earth launches academic theses with the efficiency of a World War II shipyard.

What there is of Catholic imagery in the film is accurate. But a bit more of it would have explained Tolkien's early life more clearly.

His mother, Mabel (Laura Donnelly), starts the movie by explaining to her two young sons that they are now in "impecunious circumstances" and must move from their rural home in Worcestershire. The key omission: This was a result of her having joined the Catholic Church in 1900. The family of her late husband, Arthur, a bank manager who died in 1896, cut off financial support, as did her own Baptist relatives.

Rescue came in the form of Father Francis Morgan (Colm Meaney) of the Birmingham Oratory, who became the guardian of Tolkien and his younger brother, Hilary, when Mabel died of diabetes in 1904 and saw to it that they were brought up as Catholics. "He was an upper-class Welsh-Spaniard Tory, and seemed to some just a pottering old gossip. He was -- and he was not," Tolkien wrote.

"I first learned charity and forgiveness from him; and the light of it pierced even the 'liberal' darkness out of which I came, knowing more 'Bloody Mary' than the Mother of Jesus -- who was never mentioned except as an object of wicked worship by the Romanists."

In the film, Father Francis expresses his initial disapproval of Edith Bratt (Lily Collins), with whom Tolkien (Nicholas Hoult) had fallen in love, by snorting, "She's not even Catholic!" Not then at least. Edith, whom Tolkien did not see for some time before he turned 21 because Father Francis had forbidden contact with her as an interference with his academic studies, became a Catholic before marrying Tolkien in 1916.

After that, Catholic references in the film drop away. As for the sequences of his student life at Oxford, Tolkien wrote that his first term there passed "with practically none or very little practice of religion."

The movie ends with Tolkien writing the first words of 1937's "The Hobbit." And at that point, Carpenter wrote, the author "drew upon some deeper, richer seam of his imagination than he had yet explored; and it was a seam that would continue to yield for the rest of his life."

Tolkien was a Catholic very much of his generation, his letters indicate. He was skeptical of the Second Vatican Council, and believed that St. Pius X was the greatest church reformer he'd known.

His devout view of the sacraments, however, was one Catholics of every stripe can appreciate. To his son Michael he wrote, in 1963, "I find it for myself difficult to believe that anyone who has ever been to Communion, even once, with at least right intention, can ever again reject Him without grave blame."