[Sophia the Thunder Mistress]

I am not sure that anyone in Middle-earth actually knew who or what Tom was. Indeed, I am not sure that Tolkien himself had any set idea as to how exactly Tom fitted in to the Legendarium. As you suggest, his origination as the embodiment of rural Oxfordshire doesn't really tell us much in this regard. -Saucy

If people want to export Tom Bombadil to their own mythmaking, they need take no regard for the laws of Ëa. In the meantime, Tolkien's subcreation is clear on this point. -littlemanpoet

Bombadil himself was kind of an import from earlier tales, was he not? He's something of a vestigial character (if I can borrow a term from biology) leftover from very early conceptions of the Shire. While Tolkien's "imports", like the term Atalante used for downfallen Numenor, usually have detailed and contextually appropriate meanings and developments, little (if any) is done to reconcile Tom with the rest of the Legendarium. In that case at least, Tolkien left himself miles of leeway. I'm inclined to think that there's a little leeway for us to speculate about him, even within the laws of Ea.