Grampa in Oz (1924) is the eighteenth in the series of Oz books created by L. Frank Baum and his successors, and the fourth written by Ruth Plumly Thompson. Things are going from bad to worse in the dilapidated kingdom of Ragbad; even the rag crop is failing. To top it all off (or not), King Fumbo's head is blown away in a ferocious storm (with "ten thousand pounds of thunder"). Prince Tatters of Ragbad, and Grampa, a former soldier and the bravest man in the kingdom (population 27), set out on a three-fold quest: for King Fumbo's lost head, a fortune to save the bankrupt kingdom, and a princess for Tatters to marry. They are joined by Bill, an iron weathercock from Chicago, who was brought to life by an electrical storm and blown to Oz.
Ruth Plumly Thompson (27 July 1891 – 6 April 1976) was an American writer of children's stories, best known for writing many novels placed in Oz, the fictional land of L. Frank Baum's classic children's novel The Wonderful Wizard of Oz and its sequels.