Ruth Plumly Thompson was an American author best known for her work in the Oz series, originally created by L. Frank Baum. She took over the series after Baum's death and wrote 19 books set in the magical land of Oz, starting with "Kabumpo in Oz" in 1922. Her contributions helped to expand the Oz universe and introduced new characters and adventures. Thompson was born on July 27, 1891, in Philadelphia, Pennsylvania. In addition to her Oz books, she wrote poetry and other children's stories. Her unique style and imaginative storytelling have made her an important figure in children's literature, particularly in the fantasy genre.