Tolkien Denied That This Lord Of The Rings Character Is God - But He May Be More
Tom Bombadil is a Tolkienian puzzle known only to readers of his books. Peter Jackson axed the colorful character of unknown origin from his movies, as Bombadil threw off the larger narrative and was an easy section to cut without significant repercussions. Bombadil remains an enigma (even to Tolkien), and fans have continued to debate his identity ever since he danced and sang his way onto the pages of "The Fellowship of the Ring" well over half a century ago. Some think Bombadil is the Witch-king in disguise. However, it isn't hard to debunk the idea that Frodo hangs out with one of Sauron's top servants without any negative repercussions.
Others go the other direction, positing that he's Eru Ilúvatar — the almighty being who fills the role of God, the Creator, in Tolkien's world. However, Tolkien himself denied this in a letter in 1956, where he said his iteration of the Almighty is a "monotheistic but 'sub-creational' mythology" and that in Middle-earth "there is no embodiment of the One, of God, who indeed remains remote, outside the World." In Tolkien's writings, God interferes only in select moments or through others. He doesn't appear "in the flesh," as would be the case if he were Tom Bombadil.
Okay. So ... who is Tom Bombadil, then? He's clearly important. In a letter in 1937, long before the trilogy was written, Tolkien was already referring to Bombadil as "the spirit of the (vanishing) Oxford and Berkshire countryside." In "The Fellowship of the Ring," the author ramps things up when he has the Elf-lord Glorfindel describe Bombadil as ending "Last as he was First." The capitalized titles "Last" and "First" are intriguing, but in the context that he isn't God, they only make the mystery harder to solve.
Bombadil is unexplainable and outside the story
J.R.R. Tolkien never wrote throwaway characters. It's hard to find an individual in "The Lord of the Rings," "The Hobbit," or any of the author's works who doesn't possess some kind of backstory to justify their existence in the plot. In the case of Tom Bombadil, Tolkien's biographer, Humphrey Carpenter, explains that he was "a well-known figure in the Tolkien family, for the character was based on a Dutch doll that belonged to [Tolkien's son] Michael." Michael disliked the doll and disposed of it, only for his father to save it and turn it into a hero in a one-off poem he wrote before composing "The Lord of the Rings."
When Tolkien wrote that monumental story, he included Bombadil because he already had developed him outside of Middle-earth and wanted to get him in the mix as a way to spice up the Hobbits' earlier adventures. Tolkien said as much in another letter in 1954. Even then, Tolkien pointed out that he retained the character despite the odd disruption Bombadil provides, writing, "But I kept him in, and as he was, because he represents certain things otherwise left out." He went on to explain that Tom is, in many ways, unexplainable. He interestingly referred to him as an example of "pure (real) natural science," comparing him to zoology and botany rather than cattle breeding or agriculture. Tom is a collector of knowledge, but he doesn't seek to put that knowledge into action. He's a knower, not a doer; an observer, not a participant.
Despite Bombadil's random insertion as a character with an existence and a purpose largely "outside of" the primary story, he isn't random or useless. On the contrary, his literary creator appears to have given him a lot of thought.
Tom is still really important (in an odd way)
Despite the apparent unknowns, Tolkien did have at least a partial answer to Tom Bombadil's identity. Writing for the Mythopoeic Society in 1986, Gene Hargrove posits, "It would have been impossible for Tolkien to have brought up the issue of Tom's identity and nature three times and not to have continued thinking about it until he had an answer."
In yet another letter written in 1954, Tolkien shed more light on the matter. He described Bombadil as "not an important person—to the narrative," adding, "I suppose he has some importance as a 'comment'." A bit later, he wrote, "I would not, however, have left him in, if he did not have some kind of function."
From there, at the great risk of oversimplifying Tolkien's complex approach to story creation, let's just say the author positioned Bombadil as a character who doesn't want a measure of control or domination over the larger narrative. He isn't on a "good" or a "bad" side. Tolkien even referred to Bombadil as having taken a sort of "vow of poverty" in the sense that he watches and observes without throwing his weight on one side or the other. He takes, in Tolkien's own words, "a natural pacifist view."
At the end of the day, Tolkien appears to have had thoughts on Bombadil's identity, but he was perfectly happy not to divulge them. In the same letter mentioned above, he said at an earlier point, "As a story, I think it is good that there should be a lot of things unexplained (especially if an explanation actually exists)." Shortly after this, we get the insightful line, "And even in a mythical Age there must be some enigmas, as there always are. Tom Bombadil is one (intentionally)."