Mexican Cession in the context of "Mexican California"

Utah is a landlocked state in the Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northeast, Idaho to the north, and Nevada to the west. In comparison to all the U.S. states and territories, Utah, with a population of just over three million, is the 13th-largest by area, the 30th-most populous, and the 11th-least densely populated. Urban development is mostly concentrated in two regions: the Wasatch Front in the north-central part of the state, which includes the state capital, Salt Lake City, and is home to roughly two-thirds of the population; and Washington County in the southwest, which has approximately 180,000 residents. Most of the western half of Utah lies in the Great Basin.

Utah has been inhabited for thousands of years by various indigenous groups, such as the ancient Puebloans, the Navajo, and the Ute. The first Europeans to arrive – in the mid-16th century – were the Spanish. Because of the region's challenging geography and harsh climate, it only became a peripheral part of New Spain (and later of Mexico). Even while it was Mexican territory, many of the Utah region's earliest European settlers were from the United States; notable among these were Mormons who were fleeing marginalization and persecution in the United States and arrived via the so-called Mormon Trail. In 1848, after the Mexican–American War, the region was annexed by the U.S., becoming part of the Utah Territory, which included what later became Colorado and Nevada. Disputes between the dominant Mormon community and the federal government delayed Utah's admission as a state: in 1896, after it agreed to outlaw polygamy, it was admitted as the 45th state.

The Free Soil Party, also called the Free Democratic Party or the Free Democracy, was a political party in the United States from 1848 to 1854, when it merged into the Republican Party. The party was focused on opposing the expansion of slavery into the western territories of the United States. The 1848 presidential election took place in the aftermath of the Mexican–American War and debates over the extension of slavery into the Mexican Cession. After the Whig Party and the Democratic Party nominated presidential candidates who were unwilling to rule out the extension of slavery into the Mexican Cession, anti-slavery Democrats and Whigs joined with members of the Liberty Party (an abolitionist political party) to form the new Free Soil Party. Running as the Free Soil presidential candidate, former President Martin Van Buren won 10.1 percent of the popular vote, the strongest popular vote performance by a third party up to that point in U.S. history.

Though Van Buren and many other Free Soil supporters rejoined the Democrats or the Whigs after the 1848 election, Free Soilers retained a presence in Congress over the next six years. Led by Salmon P. Chase of Ohio, John P. Hale of New Hampshire, and Charles Sumner of Massachusetts, the Free Soilers strongly opposed the Compromise of 1850, which temporarily settled the issue of slavery in the Mexican Cession. Hale ran as the party's presidential candidate in the 1852 presidential election, taking just under five percent of the vote. The 1854 Kansas–Nebraska Act repealed the long-standing Missouri Compromise and outraged many Northerners, contributing to the collapse of the Whigs and spurring the creation of a new, broad-based anti-slavery Republican Party. Most Free Soilers joined the Republican Party, which emerged as the dominant political party in the United States in the Third Party System (1856–1894).

California (/ˌkælɪˈfɔːrniə/) is a state in the Western United States that lies on the Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares an international border with the Mexican state of Baja California to the south. With almost 40 million residents across an area of 163,696 square miles (423,970 km), it is the largest state by population, third-largest state by area and the largest state economy in the U.S., with a GDP of approximately $4.1 trillion.

Prior to European colonization, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. European exploration in the 16th and 17th centuries led to the colonization by the Spanish Empire. The area became a part of Mexico in 1821, as a result of its successful war for independence. Following the U.S. conquest of California, part of the Mexican-American War, California was ceded to the United States in 1848. The California gold rush started in 1848 and led to social and demographic changes, including the California genocide. It organized itself and was admitted as the 31st state in 1850 as a free state, following the Compromise of 1850.

The Compromise of 1850 was a package of five separate bills passed by the United States Congress in September 1850 that temporarily defused tensions between slave and free states during the years leading up to the American Civil War. Designed by Whig senator Henry Clay and Democratic senator Stephen A. Douglas, with the support of President Millard Fillmore, the compromise centered on how to handle slavery in recently acquired territories from the Mexican–American War (1846–48).

The provisions of the compromise included a provision that approved California's request to enter the Union as a free state, and strengthened fugitive slave laws with the Fugitive Slave Act of 1850. The compromise also banned the slave trade in Washington, D.C. (while still allowing slavery itself there), defined northern and western borders for Texas while establishing a territorial government for the Territory of New Mexico, with no restrictions on whether any future state from this territory would be a free or slave state and established a territorial government for the Territory of Utah also with no restrictions on if the territory would become a slave or free state.

California is a state located in the Western United States. It is the most populous state and the third largest by area after Alaska and Texas. According to the 2020 United States Census, California has 39,538,223 inhabitants and 155,779.22 square miles (403,466.3 km) of land.

California has been inhabited by numerous Native American peoples for thousands of years. The Spanish, the Russians, and other Europeans began exploring and colonizing the area in the 16th and 17th centuries, with the Spanish establishing its first California mission at what is now San Diego in 1769. After the Mexican Cession of 1848, the California Gold Rush brought worldwide attention to the area. The growth of the movie industry in Los Angeles, high tech in San Francisco and Silicon Valley, tourism, agriculture, and other areas in the ensuing decades fueled the creation of a $3 trillion economy as of 2018, which would rank fifth in the world if the state were a sovereign nation.

San Jose, officially the City of San José (/ˌsæn hoʊˈzeɪ, -ˈseɪ/ SAN hoh-ZAY, -⁠SAY; Spanish: [saŋ xoˈse]), is a cultural, commercial, and political center within the San Francisco Bay Area and Silicon Valley. With a city population of 997,368 and a metropolitan area population of 1.95 million, it is the most populous city in both the Bay Area and Northern California and the 12th-most populous in the United States. Located in the center of the Santa Clara Valley on the southern shore of San Francisco Bay, San Jose covers an area of 179.97 sq mi (466.1 km) and is the county seat of Santa Clara County.

Before the arrival of the Spanish, the area around San Jose was long inhabited by the Tamien nation of the Ohlone people. San Jose was founded on November 29, 1777, as the Pueblo de San José de Guadalupe, the first city founded in the Californias. It became a part of Mexico in 1821 after the Mexican War of Independence. Following the U.S. Conquest of California during the Mexican–American War, the territory was ceded to the United States in 1848. After California achieved statehood two years later, San Jose served as the state's first capital. San Jose experienced an economic boom after World War II, with a rapid population growth and aggressive annexation of nearby communities in the 1950s and 1960s. The rapid growth of the technology industry in Silicon Valley further accelerated the city's transition from an agricultural center to an urbanized metropolitan area, prompting Mayor Tom McEnery to adopt San Jose's current motto, "Capital of Silicon Valley", in 1988. Results of the 1990 U.S. census indicated that San Jose had surpassed San Francisco in population. By the early 2000s, San Jose was California's fastest-growing economy.

San Diego (/ˌsæn diˈeɪɡoʊ/ SAN dee-AY-goh; Spanish: [san ˈdjeɣo]) is a city on the Pacific coast of Southern California, adjacent to the Mexico–United States border. It is the eighth-most populous city in the U.S. and second-most populous city in California with a population of over 1.4 million, while the San Diego metropolitan area with over 3.3 million residents is the 18th-largest metropolitan area in the country. San Diego is the county seat of San Diego County. It is known for its mild Mediterranean climate, extensive beaches and parks, long association with the United States Navy, and recent emergence as a wireless, electronics, healthcare, and biotechnology development center.

Historically home to the Kumeyaay people, San Diego has been referred to as the Birthplace of California, as it was the first site visited and settled by Europeans on what is now the West Coast of the United States. In 1542, Juan Rodríguez Cabrillo claimed the area for Spain, forming the basis for the settlement of Alta California, 200 years later. The Presidio and Mission San Diego de Alcalá, founded in 1769, formed the first European settlement in what is now California. In 1821, San Diego became part of the newly declared Mexican Empire. California was ceded to the U.S. in 1848 following the Mexican–American War and was admitted as the 31st state in 1850.

Alta California (English: Upper California), also known as Nueva California (English: New California) among other names, was a province of New Spain formally established in 1804. Along with the Baja California peninsula, it had previously comprised the province of Las Californias, but was made a separate province in 1804 (named Nueva California). Following the Mexican War of Independence, it became a territory of Mexico in April 1822 and was renamed Alta California in 1824.

The territory included all of the present-day U.S. states of California, Nevada, and Utah, and parts of Arizona, Wyoming, and Colorado. The territory was re-combined with Baja California (as a single departamento) in Mexico's 1836 Siete Leyes (Seven Laws) constitutional reform, granting it more autonomy. That change was undone in 1846, but rendered moot by the outcome of the Mexican–American War in 1848, when most of the areas formerly comprising Alta California were ceded to the U.S. in the treaty which ended the war. In 1850, California joined the union as the 31st state.