In L. Frank Baum’s The Wonderful Wizard of Oz, Dorothy’s surname is Gale.
The novel was published in 1900 and follows Dorothy Gale after a cyclone carries her and her dog Toto from Kansas to the Land of Oz. Dorothy wants to return home, so she follows the Yellow Brick Road to ask the Wizard of Oz for help.
Along the way she meets the Scarecrow, Tin Woodman, and Cowardly Lion. Each hopes the Wizard will provide something he believes he lacks: a brain, a heart, or courage. Dorothy’s journey eventually reveals that the Wizard’s public image is very different from his actual nature.
The name Gale can be missed because many adaptations emphasize “Dorothy” without regularly stating her surname. The 1939 film adaptation also adds or changes details from Baum’s book, including elements associated with Kansas and Oz. Dorothy’s surname is not Storm or West; those words may seem plausible because the story begins with a powerful cyclone and uses strong directional imagery.