Roofer in El Sobrante, CA

Between 5000 and 1000 BC, an indigenous tribe of people called the Huichin, an Ohlone people, came to the East Bay, including El Sobrante. One of the Huichin villages was located where the El Sobrante Library now stands. The Huichin left a now-buried shell mound beside San Pablo Creek. Ohlone people still live in the bay area and other parts of the world today.

Between November 1794 and May 1795, the Huichin were forcibly converted to Christianity by Spanish missionaries. After all of the Huichin were removed to Mission San Francisco, they suffered an epidemic of European diseases as well as food shortages, and died in great numbers, resulting in alarming statistics of death and escapes from the missions. In pursuing the runaways, the Franciscans sent neophytes first and (as a last resort) soldiers to go round up the runaway “Christians” from their relatives, and bring them back to the missions. Thus illness spread both inside and outside of the missions.

After Mexican independence from Spain in the early 19th century, Spanish colonists were given land grants, one of which was Rancho El Sobrante, deeded to Juan Jose and Víctor Castro in 1841. The grant’s boundaries were unusually complicated, as they were to be determined by the boundaries of the surrounding grants: San Antonio, San Pablo, El Pinole, Boca de la Cañada del Pinole, Acalanes, and La Laguna de los Palos Colorados. In this sense, the rancho was el sobrante, the remaining area. Legal disputes concerning the borders and the claims of squatters continued for four decades, with much of the land sold to pay court and attorney costs. Victor Castro was left with 549 acres (2.22 km²) of the original grant. He built an adobe dwelling in what is now El Cerrito, and became one of the first members of the Board of Supervisors of Contra Costa County. Castro died at the age of 90 in 1897. Some of his descendants still live in the area of Castro Ranch Road.