Brentwood is a city in Contra Costa County, California, United States. It is located in the East Bay region of the San Francisco Bay Area.
The population is 51,481 as of 2010, an increase of 121 percent from 23,302 at the 2000 census. Brentwood began as a community in the late 19th century, and is still known throughout the Bay Area for its agricultural products, primarily its cherries, corn and peaches. Due to urban sprawl many of the old farms and orchards have been replaced by suburban developments since 1990. Brentwood is increasingly residential, with the rate of population growth in the triple digits during the 1990s and 69% from 2000 through 2010. An official estimate showed the population increased nearly 21% during the period 2010 to 2016. Brentwood was originally laid out on land donated from property owned by John Marsh, an East Contra Costa County pioneer who acquired Rancho Los Meganos, the land grant that Brentwood is built upon, in 1837 from Jose Noriega. Marsh was one of the wealthiest men in California and was instrumental in its becoming independent from Mexico and part of the United States.