Stockton is a city in and the county seat of San Joaquin County, California, United States. It is the most populous city in the county, the 11th-most populous city in California and the 60th-most populous city in the U.S., with 320,804 residents at the 2020 census. The city is located on the San Joaquin River in the northern San Joaquin Valley, within California's Central Valley. It lies at the southeastern corner of a large inland river delta that separates it from other nearby cities, such as Sacramento and the San Francisco Bay Area. Stockton was founded by Charles Maria Weber during the California Gold Rush in 1849, after he acquired Rancho Campo de los Franceses to capitalize on its strategic location on the San Joaquin River. The city is named after famed Mexican–American War commodore Robert F. Stockton, and it was the first community in California to have a name not of Spanish or Native American origin. With the introduction of irrigation, railroad connections, and the opening of the Port of Stockton in 1933, the city developed as a logistics and commercial hub. Notable attractions in the city include the Haggin Museum and the Gurdwara Sahib of Stockton, the first Sikh house of worship established in the U.S. The University of the Pacific, chartered in 1851, is the oldest university in California and has been located in Stockton since 1923.