Where did the state name 'California' come from?

Once, a Spanish explorer who read a novel about California, he believed that it is real but according to the novel, it is a myth but the guy did not believe it's a myth, when he used the novel and set off for the exploration of California, he was determined but the Spanish Government did not to finance an exploration when it was just a myth. It is too long to explain but there's a YouTube video about this.