Dictionary.com had hot word “California” and its origins. Have a read.
Early mapmakers began labeling the “island” as California, the name of a mythical island in a book called Las Sergas de Esplandián, “The Adventures of Esplandián,” written by Garci Rodríguez de Montalvo. The book was part of a popular series of Spanish romance stories.
In the book, the mythical California is ruled by Queen Califa and populated only with female warriors who brandish gold weapons. They even harness their animals in gold because it is the only mineral on the island.