Stockton is the county seat of San Joaquin County in the U.S. state of California's Central Valley. Captain Charles Maria Weber founded Stockton in 1849 after it purchased Rancho Campo de los Franceses. The town is named after Robert F. Stockton, and it was California's first city to have a name that was not of Spanish or Native American origin. The town is located in northern San Joaquin Valley on the San Joaquin River and had an annual population of over 310,000 residents. Stockton's seaport, built during the California Gold Rush, serves as a gateway to the Central Valley and beyond. It provided convenient access to the gold mines in the South for trade and transportation. Stockton has an area of 64 miles.