So, people write Oz stories. I write Oz stories now. But most new Oz stories tend to pick up where Baum or the other Royal Historians left off and tell further adventures.
Still, there are some who go back and tell stories of Oz's past. Perhaps as a midquel, happening in between previous Oz books (often patching up what seem to be continuity gaffes), or perhaps even before The Wonderful Wizard of Oz, making it a prequel to the Oz books.
I'm actually now responsible for two prequels to The Wonderful Wizard of Oz: "The Way of a Lion," published in Oziana 2013 and "Aunt Em and Uncle Henry," a little story I posted on this blog not long ago.
Very much, both of these prequels were based on concepts I'd had for a film adaptation of The Wonderful Wizard of Oz that would flesh out the backstories of the Cowardly Lion and Dorothy. The Scarecrow tells how he was made and informed that he was brainless, and the Tin Woodman tells how he became tin, but the Lion simply tells us how he lived day to day, while we are told little information about Dorothy.
To me, what made the lion unique is that he wasn't cowardly, he simply misunderstands what courage is. According to actual accounts about male lions, they largely allow the females to do the hunting and only defend their prides when the need arises. So, it seems the Lion was actually a well-depicted anthropomorphic lion, that is, if you consider Dorothy and her friends the lion's "pride."
Since the story would start when the Lion was a baby, I had to change some things about real lions. Cubs are often raised together by a group of mothers for defense. This is because young lions are delicate and need protection, though. However, lions often live in the plains, and not in forests as lions in Oz seem to do. Thus, I assumed, given that animals in Oz speak and have come to respect each other, the danger to a cub is reduced, except from a kalidah. The trees and other features of a forest might allow a single mother to care for her cub on her own.
As one reads my story, I reveal that the Cowardly Lion is not a native Munchkin lion, but actually a Quadling. Due to a tragic point of the story, he flees to a new forest, and somehow manages to miss all other forests (I did trace his route on the International Wizard of Oz Club's map) until he comes to the Munchkin forest Dorothy will one day travel through. The main part of him being a Quadling lion was so that he actually has a story arc that begins in my story and reaches its triumph in one of the final chapters of The Wonderful Wizard of Oz. So it's as if I began a story and then let L. Frank Baum finish it, except he'd already done it over 110 years ago.
Dorothy's backstory, I knew, did not need to be complicated. I cordially dislike prequels that make out Dorothy's coming to Oz as predetermined or prophesied, or that her parents were tied to Oz somehow. What I enjoy about Baum's stories about someone from the United States going to Oz is that they were no one special when they arrived, but become known for their actions. Dorothy and the Wizard are similar in this regard, except that the people believed the Wizard to be a Wizard, but then, Dorothy was also believed to be a sorceress, the only difference is that she denied it.
The backstory for Dorothy that I wrote was actually folded into Aunt Em and Uncle Henry's, because I knew they had to be tied to each other. How they met was actually based on how my maternal grandparents met. All the names I gave them were either from Baum's life or my grandparents. "Carpenter" was the married name of one of Maud Baum's sisters, so I gave it to Uncle Henry, while Em's maiden name "Stanton" was from an uncle of Baum's. Aunt Em's middle name "Marie" was my grandmother's name. "Matilda" is of course the name of L. Frank Baum's mother in law, while "Charles" is from Charles Dickens, one of Baum's favorite authors. (It's also been suggested that "Oz" came from Dickens' nickname "Boz.")
The difficult part was finding out how Dorothy became an orphan. I had decided to tie Charles' death to the sinking of the USS Maine, the event that set off the Spanish-American War. This was with the idea that The Wonderful Wizard of Oz takes place in 1900. Matilda's death was harder to decide on. I suppose I could have made it easy and had Matilda die during childbirth, thus Charles had to leave Dorothy with Aunt Em and Uncle Henry when he had to serve his country anyway, but I'd decided that Matilda would die after Charles.
My main intention was that after Charles died, Dorothy and her mother would move in with Aunt Em and Uncle Henry. Matilda would die on the farm somehow in an accident that Uncle Henry could have possibly avoided. He'd then blame himself for her death, leading to his rarely speaking in Wonderful Wizard. But there wasn't really a good opening without making him look like a really negligent farmer. I did once take a page from Baum's short story "The Diamondback" and have Matilda save Dorothy from a rattlesnake that bites her instead, except that snake venom isn't that fast acting, and surely Uncle Henry and Aunt Em could have been informed and treated it before it proved lethal.
One person suggested that a sinkhole open on the farm and Matilda gets caught in it while rescuing Dorothy. That seemed a bit much, however. So, in the story I posted on the blog, Matilda's death is left vague. I just can't seem to kill Matilda...