The Californias (Spanish: Las Californias), occasionally known as The Three Californias or Two Californias, are a region of North America spanning the United States and Mexico, consisting of the U.S. state of California and the Mexican states of Baja California and Baja California Sur. Historically, the term Californias was used to define the vast northwestern region of Spanish America, as the Province of the Californias (), and later as a collective term for Alta California and the Baja California Peninsula. Originally a single, vast entity within the Spanish Empire, as the Californias became defined in their geographical limits, their administration was split various times into Baja California (Lower California) and Alta California (Upper California), especially during the Mexican control of the region, following the Mexican War of Independence. As a part of the Mexican–American War (1846–48), the American Conquest of Alta California saw the vast Alta California territory ceded from Mexico to the United States. The populated coastal region of the territory was admitted into the Union in 1850 as the State of California, while the vast, sparsely populated interior region would only later gain statehood as Nevada, Utah, and large parts of Arizona, Wyoming, Colorado and New Mexico. Today, Californias is a collective term to refer to the American and Mexican states bearing the name California, which share geography, history, cultures, and strong economic ties. Etymology There has been understandable confusion about use of the plural Californias by Spanish colonial authorities. California historian Theodore Hittell offered the following explanation: History The first attempted Spanish occupation of California was by the Jesuit missionary Eusebio Kino, in 1683. His Misión San Bruno failed, however, and it was not until 1697 that Misión de Nuestra Señora de Loreto Conchó was successfully established by another Jesuit, Juan María de Salvatierra. The mission became the nucleus of Loreto, first permanent settlement and first administrative center of the province. The Jesuits went on to found a total of 18 missions in the lower two-thirds of the Baja California Peninsula. Province of New Spain In 1767, the Jesuits were expelled from the missions, and Franciscans were brought in to take over. Gaspar de Portolá was appointed governor to supervise the transition. At the same time, a new visitador, José de Gálvez, was dispatched from Spain with authority to organize and expand the fledgling province. The more ambitious province name, Las Californias, was established by a joint