A hobbit is a measure of weight equal to 168 pounds (or 4 Welsh Pecks). Probably, you expected a different definition for a hobbit. I have read that English writer J.R.R. Tolkien was fascinated with the Welsh language and customs, to the point that he designed his fictional Elf language on Welsh meanings, words, and traditions. When Wales became part of the United Kingdom in 1707 (after a long and difficult transition), that did not mean that the Welsh people got in line and did what they were told to do. In particular, very independent Welsh language and culture endures today, and this is not just OK, cultural identity, once put down as rebellion, is now encouraged in all members of the United Kingdom.
Tolkien said that he worked on “The Hobbit” manuscript for 2.5 years, intending the story to be a fairy tale for adults to read to children. Indeed, his creation of a “halfling” relative of mankind resulted in child-sized adults who had physical features that seemed to belong on full-sized humans (large feet, noses, ears, and sometimes hands). In that, he walked a fine line as a writer. The hobbits, in appearance and in their simple ways were intended to amuse children, and possibly enable their parents to explain the importance of accepting and loving people who look different. Still, some prejudices against little people crept into Tolkien’s hobbit adventures when both humans and other humanoids (elves, dwarves, orks, etc.) considered hobbits to be unwise, uncommitted, and that they generally did not matter. Even Bilbo Baggins wrote down such observations about his own kind in his book.
How did an intended children’s story become a series of violent tales of war? I have read that Tolkien placed his horrifying experiences as a British soldier in WWI into the stories. I don’t see that. He began writing The Hobbit 12 years after WWI ended and before WWII began. My theory is that The Hobbit had to contain action and tales of human misery in order to appeal to adults. After all, the adults who would purchase the book would see that it contained way too much detail for children to comprehend or to sit still and have it read to them. The horror in the book seemed to work for those who read it (Many adults could not sit still to read it either). But, there was a low hum of public interest in the story that Tolkien wrote, a measure of its success through constant badgering that Tolkien endured, driving him to continue the tale in one or more additional books.
As Tolkien revived The Hobbit, the story evolved into the darker “Lord of the Rings” series. A fiction writer typically begins with a theme, then adds a setting and characters to bring the theme alive. It is the plot that intrigues the reader, and good writers obscure the plot or even hide it, so that the story unfolds in an unpredictable way. This is how the reader is kept interested, on edge, forced to imagine where the story is going, because the author did not give the answer early in the book. Tolkien gave away the plot early in “The Lord of the Rings.” The entire story was about another hobbit who agreed to save “Middle Earth” by agreeing to toss a ring into lava. But, remember that Tolkien thrived on creating details. By revealing the plot, he permitted himself to explain the entire made up history of walking talking trees, ruined elves, wizards that arise from death, dwarves that mine armored clothing, etc. He also empowered himself to breath life into many characters in the series.
As characters act out their roles, something unexplainable happens that only another writer can appreciate it. The characters tend to take on a life of their own, and it is they, acting within their character, who wrestle with the author about what they will do next. They will “attempt” to take the story to a conclusion different from the one the author intended. A disciplined writer reigns them in. An author will rewrite a nearly finished work of fiction if he or she realizes that the story has unfolded untrue to the plot. But, how could undisciplined characters ruin a plot that simply requires a ring to be tossed into lava? They can’t. Problem solved.