Frank Baum's widow Maud Baum's blessing, the series was continued by five different authors (with Ruth Plumly Thompson, the first to continue the series, eventually publishing more Oz books than even Baum). He wrote a total of 14 books before his death in 1919. Reilly & Lee convinced him to write an additional four books, and Baum attempted to end the series after book six, only to be forced to return to the series three years later after some poor theater investments and poor sales on his other fantasy series starring the characters Trot and Cap'n Bill (who were later imported into the Oz books). Frank Baum wrote the second book only to capitalize on the success of the stage version of The Wonderful Wizard of Oz.

The book has had 39 official sequels published by Reilly & Lee, with the originals generally being called 'The Famous Forty', 13 of the sequels being written by Baum, and 35 books illustrated by John R.

Frank Baum in his novel The Wonderful Wizard of Oz. The Land of Oz is a fantasy setting created by L.

How many books in wizard of oz series