What Bizarre Error Gave California Its Name? When the Spanish first began exploring the Pacific Coast of North America, they mistakenly believed that California was an island. (Some of the earliest and most fascinating maps of the state depict it as separated from the mainland.) This is considered one of the greatest, albeit short-lived, cartographic errors. 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. The legend of Califa and her island was well known among New World explorers. In 1536 when Hernán Cortés arrived in Baja California, he believed he had landed on the legendary island. Over three hundred years later gold was discovered in California, making the legend partially true and earning the state its nickname: The Golden State.