This post contains spoilers for The Giant Horse of Oz.
What we do know about her is that she was a little old woman who dressed in white and wore a peaked hat. I've also concluded that because she sends Dorothy to see the Wizard that she—unlike Glinda—was unaware that the Wizard wasn't actually what he seemed to be.
The Good Witch of the North, from her one chapter in Baum's work, appears to be level-headed and very wise, though she never suspected the Wizard of being a fraud. Still, it's proved difficult for people adapting the story to not give her a few quirks. MGM had her giggle and admit to being "a little muddled." The original stage version of The Wiz reinvented her as the hilarious Addaperle the Feel Good Girl, while the film made her a bag lady called Miss One.
In the original musical extravaganza adaptation of the story, she appears to be not quite so old and quite a bit more like Glinda (who I understand was mentioned in some versions of the play, but not seen). She has the name Locosta (or Locousta), and she gives Dorothy a ruby ring that will grant her three wishes while in Oz. (It can't take her out of Oz, so this was rather like the Silver Shoes and the Golden Cap combined into one item.) Some fans have adopted "Locosta" as her name in their works or personal preferred version of Oz continuity. I personally like the name myself.
The Good Witch of the North, no matter how sweet or gentle she may appear to be, is not someone to offend. She gives Dorothy a kiss that marks her as being under her protection. (This kiss surprisingly never leaves Dorothy, Thompson reveals in The Wishing Horse of Oz, though Dorothy had been in plenty of trouble many times before with it playing no role.) This mark saves Dorothy from being abused by the Winged Monkeys, and perhaps would have kept the kalidahs, wolves, crows, bees, the Winkies, the Fighting Trees, the Hammerheads and the Great Spider away if they had actually been able to try to harm her.
Unlike Glinda, who holds transformations to be dishonest, the Good Witch of the North isn't so scrupulous, though she only transforms non-living things. She transforms her hat into a slate that gives advice, and in her brief and only Baum-penned reappearance in The Road to Oz, she performs a spectacle at Ozma's birthday party:
The Good Witch of the North amused the people by transforming ten stones into ten birds, the ten birds into ten lambs, and the ten lambs into ten little girls, who gave a pretty dance and were then transformed into ten stones again, just as they were in the beginning.The Marvelous Land of Oz mentions her, but only that the Good Witch who ruled the Gillikins forbade any other witches in her domain. (Which Mombi tries to get around due to a technicality.) Dorothy and the Wizard in Oz tells us that she actually conquered Mombi.
The Good Witch of the North doesn't reappear until Thompson's The Giant Horse of Oz when Prince Philador of the Ozure Islands goes to see her for help, but when he arrives, she has had a sudden thought and jumped through the Witch Window. Her slate says that she will never return. She also has the odd name Tattypoo. However, it's revealed that she's actually been the missing Queen Orin of the Ozure Islands all this time. Mombi tried to turn her into a witch, but her inner goodness was too great to turn wicked, so she was a good witch and conquered Mombi.
Neither Orin nor the Good Witch of the North really has a role in the rest of the Famous Forty Oz books, though Orin is one of the guests during the grand celebration in The Wishing Horse of Oz, but in Jack Snow's The Magical Mimics of Oz, the Good Witch of the North is mentioned as attending a celebration at the end of that book. Jack Snow very much ignored Thompson's additions to Oz, and except for this (and a couple hiccups in The Shaggy Man of Oz), his "back to Baum" approach didn't really cause any issues.
Not all Oz fans have been fans of the fact that Thompson did away with one of Baum's characters and didn't really do anything with her. Some have specifically disagreed with the view that you had to be young and pretty to be happy. (There are Oz fans who are getting along in their years who are very happy, thank you very much!)
Oz fan David Hardenbrook wrote a book titled Locosta and the Unknown Witches of Oz that offered a reconciliation. Basically, rather than turning Orin into a witch, Mombi used the same "switching" spell that Baum describes Mombi using on Jellia Jamb and herself in The Marvelous Land of Oz. The real Locosta was in the Great Outside World with Orin's looks and soon became a movie star. When the spell was broken, she resumed her old form and became a librarian. Eventually, she met hero Dan and returned to Oz. If this had been the story, it could have fit into Oz continuity just fine. Unfortunately, Hardenbrook included many new details for his version of Oz that are contrary to other fan's ideas. While the story is entertaining on its own, it's difficult to fit peacefully into Oz canon.
It's also problematic that Giant Horse says that Orin has been missing for twenty-five years. Unless the previous 21 Oz books took place in at least the last 15 of those years (which is possible, do you really think only one adventure a year happens in Oz?), then Mombi must have enchanted Orin after Dorothy arrived in Oz the first time. That's a little too close to The Marvelous Land of Oz, particularly after the timeline I set up in my blog about Dorothy.
Jack Snow may have had an answer to the Tattypoo/Orin/Good Witch of the North debacle. In Who's Who in Oz, he claimed that Tattypoo only thought that she was the Good Witch of the North. The Good Witch is listed separately, and her entry says:
Dorothy says that some pretty important things have transpired involving the Good Witch of the North, but the story is just too long to crowd into a small space. It would take a whole book, Dorothy tells us.Perhaps his lost or unfinished or unwritten third Oz book may have included the Good Witch of the North, and he may have taken a jab at explaining how she was still around despite Giant Horse. If the book ever turns up, Oz fans will be only too glad to see it.
So, what about you? In your personal view of Oz continuity, does the Good Witch of the North still exist? Is she Tattypoo or Locosta or another name entirely?