Soon after the Gold Rush began in California, gold was found along the banks of the Mokelumne, Calaveras, and Stanislaus Rivers. Murphys, Angels Camp, Mokelumne Hill, and many other mining camps quickly popped up surrounding gold strikes.

Vallecito, meaning “Little Valley” was named by Mexican miners. Carson Hill was named for James Carson who an early miner in the area. San Andreas was named for the Hispanic Church established there during this time. Copper was found near Copperopolis, where it would later be utilized in the Civil War to produce shell casings for the Union Army in the North.