Santa Rosa (Spanish for ‘”Saint Rose”‘) is a city in and the county seat of Sonoma County. Its estimated 2019 population was 176,753. Santa Rosa is the largest city in California’s Redwood Empire, Wine Country and the North Bay; the fifth most populous city in the San Francisco Bay Area after San Jose, San Francisco, Oakland, and Fremont; and the 27th most populous city in California. Santa Rosa was founded in 1833 and named after Saint Rose of Lima. Before the arrival of Europeans, the Santa Rosa Plain was home to a strong and populous tribe of Pomo natives known as the Bitakomtara. The Bitakomtara controlled the area closely, barring passage to others until permission was arranged. Those who entered without permission were subject to harsh penalties.
The first known permanent European settlement of Santa Rosa was the homestead of the Carrillo family, in-laws to Mariano Guadalupe Vallejo, who settled the Sonoma pueblo and Petaluma area. In the 1830s, during the Mexican period, the family of María López de Carrillo built an adobe house on their Rancho Cabeza de Santa Rosa land grant, just east of what later became downtown Santa Rosa. Allegedly, however, by the 1820s, before the Carrillos built their adobe in the 1830s, Spanish and Mexican settlers from nearby Sonoma and other settlements to the south raised livestock in the area and slaughtered animals at the fork of the Santa Rosa Creek and Matanzas Creek, near the intersection of modern-day Santa Rosa Avenue and Sonoma Avenue.
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