Vallecito is where gold was discovered on Coyote Creek by John and Daniel Murphy in the earliest years of the Gold Rush. The source of the riches was the ancient river channel on which the town is situated. The name Vallecito, the diminutive of the Spanish "valle" (valley), is found on historic maps with a great variety of spellings. Many large nuggets were located and good strikes were made in the early 1850s in the community and the surrounding area. Much mining was carried out by “coyoteing” (excavating short shafts down to gold-bearing leves), but when rainstorms flooded the shafts, most miners turned to more organized placer mining. By the mid-1860s no more major strikes were located, but hydraulic mining was carried on extensively in the vicinity beginning in the 1870s. In 1880 the town was the second largest gold producer in the county, exceeded only by Mokelumne Hill. Drift mining was carried on in the district in the 1930s, and the bed of Coyote Creek was dredged.

A post office was established in 1854 and numerous frame and stone buildings erected. Much of the town was destroyed by fire in 1859 and not rebuilt. The most enduring of the 1850s buildings, the stone Dinkelspiel Store (Cohen & Levy), is located at the south end of Main Street, while the stone Cuneo Store is in ruins. Other early buildings remaining in town include the Community Church and several residences dating from the 1850s to the 1920s (Gudde 1975:358).