One thing for which Oz is known is its collection of magically animated beings. In that fairyland, anything from a scarecrow to a footstool to a painting can come to life, always with its own distinct personality. The first book introduces as to the Scarecrow and the Tin Woodman, as well as a town of living china figurines. We're never told how the Scarecrow came to life, although Ruth Plumly Thompson took a crack at it in The Royal Book of Oz. And as you probably know by now, the Tin Woodman's origin is reminiscent of Theseus' Paradox, in that he was a flesh-and-blood person who gradually had all of his body parts replaced with tin, yet retained the same consciousness. L. Frank Baum reused that idea for the General of Phreex, a bit character in John Dough and the Cherub who lost various body parts in battle, and had replacements made of various substances. His head is now wax, his legs cork and basswood, and his arms rubber.
It's in Land that Baum first gives us a viable means for bringing lifeless matter to life, a magical compound known simply as the Powder of Life. Invented by a crooked magician named Dr. Pipt, this powder is responsible for animating the Glass Cat, Jack Pumpkinhead, the Sawhorse, the Gump, the Blue Bear Rug, the Patchwork Girl, and Victor Columbia Edison; not to mention numerous other characters in apocryphal stories. Also, in Cowardly Lion, the stone man Crunch says that the Wizard Wam brought him to life with powder from a shaker. Did Wam obtain this from Pipt, or did he create a similar powder? This powder also made its way into the Russian Magic Land books, in which Urfin Jus uses it to bring his army of Deadwood Oaks to life.
In Emerald City, we come across the Cuttenclips, live paper dolls made by Miss Cuttenclip, who had obtained living paper from Glinda. How the Sorceress had this paper in the first place isn't clear, considering that I don't think she's ever credited with animating anything else, but I'm sure Glinda has a lot of powers we don't know about. With most of the other small communities of normally inanimate objects, going back to the china people in Wizard, we're really not given any indication how they came to exist. Thompson continues that tradition, but also introduces a few more characters who were animated in somewhat more unorthodox ways. Bill the Weather-Cock claims that he came to life when he hit an electrical wire during a thunderstorm, which sounds rather unlikely even when I'm wearing my Suspension of Disbelief cap, but this explanation did come from an era when people thought electricity could do just about anything. Dorothy brings Humpy the dummy to life with some wishing sand from Wish Way. And perhaps the oddest of all is the statue Benny in Giant Horse. Here, we're told that the owner of a Boston thrift shop found a book in a second-hand coat (bought, as per narrative description, from "a dusky gentleman in Grant Street"), just happened to read from it in front of a statue in the park, and what he read brought to statue to life. There's an awful lot of coincidence involved there, and I think it might also be the only case of someone in the Oz books bringing an inanimate object to life simply through words, with no tools involved.
John R. Neill's books have so many objects showing signs of life that it kind of cheapens the idea. In a land where houses fight and shoes sing, a live scarecrow becomes much less interesting. There's never any explanation for this abundance of life, either. Snow's books tell us that both Princess Ozana and Conjo brought wooden people to life, but again don't explain how. It seems that there must be several ways to bring objects to life, but the fact that the Powder of Life is seen as so valuable must mean that access to them is difficult, even for more accomplished magic-workers.