Los Angeles (pronounced /lɒs ˈændʒələs/ los-AN-jə-ləs; Spanish: [los ˈaŋxeles], Spanish for "The Angels") is the second largest city in the United States, and with a population of 3.8 million is the largest city in the state of California and the Western United States. Additionally the city spans over 498.3 square miles (1,290.6 km) in Southern California and is anchored to the world's 13th largest metropolitan area with 17.7 million people spread out over much of coastal Southern California. The Los Angeles–Long Beach–Santa Ana metropolitan area is home to nearly 12.9 million residents. Los Angeles is also the seat of Los Angeles County, the most populated and one of the most multicultural counties in the United States. The city's inhabitants are referred to as "Angelenos" (/ændʒɨˈliːnoʊz/).

Los Angeles was founded on September 4, 1781, by Spanish governor Felipe de Neve as El Pueblo de Nuestra Señora la Reina de los Angeles del Río de Porciúncula (The Village of Our Lady, the Queen of the Angels of the river of Porziuncola). It became a part of Mexico in 1821, following its independence from Spain. In 1848, at the end of the Mexican-American War, Los Angeles and the rest of California were purchased as part of the Treaty of Guadalupe Hidalgo, thereby becoming part of the United States; Mexico retained the territory of Baja California. Los Angeles was incorporated as a municipality on April 4, 1850, five months before California achieved statehood.

Often known by its initials, L.A., and nicknamed The City of Angels, Los Angeles is a world center of business, international trade, entertainment, culture, media, fashion, science, technology, and education. It is home to renowned institutions covering a broad range of professional and cultural fields, and is one of the most substantial economic engines within the United States. In 2008, Los Angeles was named the world's eighth most economically powerful city by Forbes.com, ahead of Shanghai and Toronto but behind New York City and London. As the home base of Hollywood, it is known as the "Entertainment Capital of the World", leading the world in the creation of motion pictures, television production, video games, and recorded music. The importance of the entertainment business to the city has led many celebrities to call Los Angeles and its surrounding suburbs home.