In prehistoric times the valley was inhabited by the Patwin Native Americans, with possible habitation by Wappo tribes in the northwestern foothills. Most villages are thought to have been constructed near the floodplains of watercourses that drain the valley. These people were called Diggers and their food consisted wild roots, acorns, small animals, earthworms, grasshoppers, and bread made from crushed California buckeye kernels. In winter they would construct huts made of tree branches. In summer they camped near rivers and streams. In winter months, they were half clad in wild animal skins and at other times they wore no clothing. The maximum prehistoric population is thought not to have exceeded 5000 persons.
In 1776 a fort was erected by the Spanish Governor, Felipe de Neve a short distance northwest of Napa, on an elevated plateau. Russians from Sonoma County's Fort Ross grazed cattle and sheep in the Napa Valley in the early 1800s and in 1841 a survey party from the fort placed a plaque on the summit of Mount Saint Helena.
Francis Castro and Father Jose Altimura were the first Europeans to explore the Napa Valley in 1823. When the first white settlers arrived in the early 1830s, there were six tribes in the valley speaking different dialects and they were often at war with each other. The Mayacomos tribe lived in the area where Calistoga was founded. The Callajomans were in the area near where the town of St. Helena now stands. Further south, the Kymus dwelt in the middle part of the valley. The Napa and Ulcus tribes occupied part of the area where the City of Napa now exists while the Soscol tribe occupied the portion that now makes up the southern end of the valley. Many of the native peoples died during a small-pox epidemic in 1838. Settlers also killed several over claims of cattle theft.
During the era between 1836 and 1846 when California was a province of independent Mexico, the following 13 ranchos were granted in Napa County: Rancho Carne Humana, Rancho Catacula, Rancho Caymus, Rancho Chimiles, Rancho Entre Napa, Rancho La Jota, Las Putas, Rancho Locoallomi, Rancho Napa, Rancho Tulucay, Rancho Yjome, Rancho Huichica, Rancho Mallacomes.
Napa Valley Pioneers
George Calvert Yount was an early settler in Napa County and is believed to be the first Anglo-Saxon resident in the county. In 1836 Yount obtained the Mexican grant Rancho Caymus where he built what is said to be the first log house in California. Soon afterward, he built a sawmill and grain mill, and was the first person to plant a vineyard in the county. Following Yount's death in 1865 at age 71, the town of Yountville was named in his honor. Following his marriage to General Vallejo’s niece Maria Guadalupe Soberanes, Edward Turner Bale became a citizen of Mexico and was granted Rancho Carne Humana in the northern end of the valley. Bale completed building the Bale Grist Mill a few miles north of St. Helena in 1846. Colonel Joseph B. Chiles a guide for one of the earliest immigrant trains to California, was granted Rancho Catacula in 1844. The Town of Napa was founded on Rancho Entre Napa by Nathan Coombs in 1847.
Mexican Cesssion / Growth
Following the event of the Mexican–American War, Bear Flag Revolt in 1846 and the Mexican Cession in 1848, settlers were granted deeds from the original ranchos during the 1850s through 1870s. To this day, a number of streets and landmarks around the valley reflect the names of these ranchos and original grantees.
The county's population began to swell in mid century as pioneers, prospectors and entrepreneurs moved in and set up residence. During this period, settlers primarily raised cattle, farmed grain and fruit crops. Mineral mining also played a role in the economics of the county. While gold was being prospected in other areas of the state in the 1850s, Napa County became a center for silver and quick silver mining. In 1866 John Lawley established a toll road from Calistoga over Mount Saint Helena to Lake County.
Early Agriculture
Napa Valley is now known mostly for its premier wines. In the beginning, white settlers planted vineyards with cuttings supplied by Catholic priests from Sonoma and San Rafael. In 1861, Riesling cuttings were introduced to the Valley and, from these small beginnings, Napa Valley has become noted as one of the premier wine-making regions of the world.Descendents of George Yount and Edward Bale played key roles in the early development of Napa County's wine industry. Yount's granddaughter Elizabeth Yount married Thomas Rutherford in 1864. The couple received as a wedding gift from George Yount, land in the area of the valley now known as Rutherford. Rutherford established himself as a serious grower and producer of fine wines in the following years. Bale's daughter Caroline married winemaker Charles Krug in 1860. Bale provided a dowry that included land north of St. Helena. Krug planted a vineyard and established the valley's first commercial winery on this land.
By the end of the 20th century's first decade farmers had also planted over 500,000 fruit and nut trees in the county. This helped to soften the blows to the agricultural economy caused by the phylloxera infestation in the county's vineyards and upcoming prohibition that crippled the wine industry. Napa Valley was most noted for prune trees until vineyards became the primary crop in the mid 1900s.
edited source: wikipedia.org/Napa County/Napa Valley