Baum's novel, The Wonderful Wizard of Oz.

The Wizard of Oz was first turned into a musical extravaganza by Baum himself. A loose adaptation based on his 1900 novel, The Wonderful Wizard of Oz
first played in Chicago in 1902, and was a success on Broadway the following year. It then toured for nine years.

The 1939 film adaptation bore a closer resemblance to the storyline of Baum's original novel than most previous versions. It was a strong success, winning the Academy Awards for Best Original Song and Original Score, and continues to be broadcast perennially.