During his expedition to complete the chain of missions in California in 1772, Father Juan Crespi named a small river in honor of San Benidicto ( Saint Benedict), the patron saint of the married. The area surrounding the river became known as the San Benito Valley. Some 25 years later on June 24, 1797 Father Fermin Francisco de Lasuen christened the mission at San Juan Bautista in the northwestern part of what was later to become San Benito County.

On February 12, 1874 Governor Newton Booth, signed a bill creating a new county from part of Monterey county and named it after the valley. The county seat was established 7 miles east of San Juan Bautista in the rapidly growing town of Hollister.

The county population grew so quickly that 13 years later the State Legislature expanded the county boundaries and parts of Merced and Fresno counties were incorporated into it. The boundaries have remained unchanged since 1887.

San Benito County is a county located in the California Coast Range Mountains south of San Jose. As of 2000 the population was 53,234. The county seat is Hollister. As housing costs have gone up in the San Francisco Bay Area, commuters have begun moving to San Benito County.