Partition and secession in California
California, the most populous state in the United States and third largest in area after Alaska and Texas, has been the subject of more than 220 proposals to divide it into multiple states since its admission to the United States in 1850, including at least 27 significant proposals in the first 150 years of statehood. In addition, there have been some calls for the secession of multiple states or large regions in the American West (such as the proposal of Cascadia) which often include parts of Northern California. Prior California partitions. California was partitioned in  its past, prior to its admission as a state in the United States. What under Spanish rule was called the Province of Las Californias (1768–1804), which stretched almost from north to south, was divided into Alta California (Upper California) and Baja California (Lower California) in 1804 on a line separating the Franciscan missions in the north from the Dominican missions in the south, with Misión San Miguel Arcángel de la Frontera set as the northern limit of Baja California and the southern limit of Alta California. After the Mexican–American War lasting from 1846 to 1848, most of Alta California  would be partitioned into five U.S. states, with the western portion of Alta California admitted to the United States as the present-day State of California, and later partitions of Alta California to become Nevada, Utah, and parts of Arizona and Wyoming. Baja California Territory would absorb what was left of Alta California (which included the modern-day cities of Tijuana and Mexicali) and remained under Mexican rule. The territory was subsequently divided into two Mexican states in 1931. In 1888, under the government of President Porfirio Díaz, Baja California became a federally administered territory called the North Territory of  Baja California ("north territory" because it was the northernmost territory in the Republic of Mexico). In 1952, the northern portion of this territory (above 28°N) became the 29th state of Mexico, called Baja California; the sparsely populated southern portion remained a federally administered territory. In 1974, it became the 31st state of Mexico, admitted as Baja California Sur. History of partition movements. Pre-statehood. The territory that became the present state of California was acquired by the U.S. as a result of American victory in the Mexican–American War and subsequent 1848 Mexican Cession. After the war, a  confrontation erupted between the slave states of the South and the free states of the North regarding the status of these acquired territories. Among the disputes, the South wanted to extend the Missouri Compromise line (36°30' parallel north), and thus slave territory, west to Southern California and to the Pacific coast, while the North did not. Starting in late 1848, Americans and foreigners of many different countries entered into California in unprecedented numbers, for the California Gold Rush, rapidly increasing the population. In response to growing demand for a better, more representative government, a Constitutional Convention was held  in 1849. The delegates there unanimously outlawed slavery, and therefore had no interest in extending the Missouri Compromise Line through California; the lightly populated southern half had never had slavery and was heavily Hispanic. Delegates applied for statehood with the current boundaries. As part of the Compromise of 1850, Congressional representatives of the American South reluctantly acceded to having California be a free state, and it officially became the 31st state in the union on September 9, 1850. Post-statehood. Southern California attempted three times in the 1850s to achieve a separate statehood or territorial status from Northern California. Union  with other states. Ecotopia. Writer Ernest Callenbach wrote a 1975 novel, entitled "Ecotopia", in which he proposed a full-blown secession of Northern California, Oregon, and Washington from the United States in order to focus upon environmentally friendly living and culture. He later abandoned the idea stating: "We are now fatally interconnected, in climate change, ocean impoverishment, agricultural soil loss, etc. etc. etc." The premise was borrowed / adapted by Starhawk for her novel "The Fifth Sacred Thing" (1993), which pitted the eco-feminist inhabitants of a future, independent San Francisco against a rival, right-wing polity centered on Los Angeles . Cascadia. While mostly consisting of Washington, Oregon, Idaho and British Columbia in Canada, proposals for an independent Cascadia often include portions of northern California. Californian reunification. The idea of a united California often consisting of modern-day California, Baja California, and Baja California Sur, or the former lands previously governed by the Province of Las Californias (1767-1804). There were fears during the Magonista rebellion of 1911 from both Americans and Mexicans of a Magonista expansion into California from, then Magonista-controlled, Baja California that would establish anarcho-communism across the Californias and inspire rebellions from Indigenous Californians against the  US and Mexican governments. Californian independence. Prior to American annexation, one instance of a Californian independence movement from a sovereign nation occurred when the California Republic was declared independent from the Centralist Republic of Mexico in 1846 during the Bear Flag Revolt during the Mexican–American War. After American annexation, there had been little to no independence movements prior to the Election of Donald Trump. Numerous organizations advocate for the independence of California as a sovereign state. Common arguments in support of independence are often based on the fact of California having the fifth-largest economy in the world, and  for being home to the global centers of entertainment (Hollywood) and technology (Silicon Valley). California National Party. Founded in 2015, California National Party (CNP) is a political party advocating a pragmatic platform. The CNP also seeks, as a long-term goal, the secession of California from the United States by legal and peaceful means. The name and mission of the California National Party are partly inspired by the Scottish National Party, a social democratic, civic nationalist, center-left party advocating progressivist policies and independence for Scotland. California Freedom Coalition. The California Freedom Coalition is a political group, founded in 2017 , advocating for the political, economic, and social empowerment of Californians. It supports universal healthcare for Californians, greater representation for California in the U.S. Congress, and more funding for education in California, as well as the possibility of Californian independence. Yes California. In the wake of Republican nominee Donald Trump's winning the 2016 presidential election, a fringe movement organized by Yes California, referred to as "Calexit"—a term inspired by the successful 2016 Brexit referendum—arose in a bid to gather the 585,407 signatures necessary to place a secessionist question on the 2018 ballot. In July 2018, the objectives of the  Calexit initiative were expanded upon by including a plan to carve out an “autonomous Native American nation” that would take up the eastern part of California, and "postponing its ballot referendum approach in favor of convincing Republican states to support their breakaway efforts." "Yes California" was founded by Louis J. Marinelli, a New Yorker who moved to Russia, and was supported by the Russian government.