The etymology of "California" is so interesting it gets its own Wikipedia page, something I've only seen for OK before now. When California was discovered in 1542, it was thought to be the mythical island predicted by the 1510 Spanish novel Las Sergas de Esplandián, a wildly popular fantasy book in which there was a paradise isle east of Asia covered with fierce and strong native women. By the time the conquistadors realized that what we call Baja California is a peninsula and not an island, it was too late and the name had stuck. But where did the name in the book come from? It's thought that the author created the toponym from the Arabic word khalifa, meaning "caliph" (so California literally means "land of the Caliph". This comes from khalif, "successor", from the verb khalafa, "to succeed", from the root k-l-f, having to do with transition. This in turn is of Proto-Semitic origin- possibly from the reconstruction halap, meaning "to go beyond".
Adam Aleksic, a rising sophomore studying linguistics and government at Harvard University, has been described as the internet's sixth most famous etymologist. He also has disturbing interests in politics, vexillology, geography, board games, conlanging, and law.