The area that is now Brentwood was part of the Rancho San Vicente y Santa Monica, a Spanish land-grant ranch sold off in pieces by the Sepulveda family after the Mexican-American War. Development began following the establishment of the large 600-acre (2.4 km2) Pacific Branch of the National Home for Disabled Soldiers and Sailors in the 1880s. A small community sprung up outside that facility's west gate, taking on the name 'Westgate'. Annexed by the City of Los Angelese on June 14, 1916, Westgate's 127 km? (49 mi?) included large parts of what is now the Pacific Palisades and a small portion of today's Bel-Air. Westgate Avenue is one of the last reminders of the area's former namesake.
Originally planted with soybeans and avocados, Brentwood is now one of the prominent districts of the Westside and among the wealthiest neighborhoods in all of Los Angeles. It has prosperous commercial districts along each of its major east-west thoroughfares, Wilshire Boulevard, San Vicente Boulevard and Sunset Boulevard, and is largely populated by professionals and executives.
Though there is no direct connection, the name Brentwood harks to Brentwood of Essex, England, a town on the outskirts of London dating back to Saxon times. Many local streets reflect this ersatz British heritage, including Barrington, Gorham, and Bristol.
Local traditions include the annual decoration of San Vicente Boulevard's historic coral trees with holiday lights and a Maypole erected each year on the lawn of the Archer School for Girls, carrying on the tradition set by the Eastern Star Home that it replaced. Inspired by the community of veterans resident at the former Soldiers and Sailors Home, now a United States Department of Veterans Affairs Medical Center, Brentwood once regularly hosted a Memorial Day parade, complete with a string of classic cars and an elephant named Tiny; the tradition is now only sporadically practiced due to funding.
Brentwood, like nearby Santa Monica, has a temperate climate influenced by marine breezes off the Pacific Ocean. Residents frequently wake to a "marine layer," a cover of clouds brought in at night which burns off by mid-morning. The topography is generally split into two characters, broadly divided by Sunset Boulevard: the area north of Sunset is defined by ridges and canyons of the Santa Monica Mountains; south of Sunset the area is relatively flat. The southern district features underground springs which bubble up into a small creek along "the Gully" near the Brentwood Country Club, and in the "Indian Springs" portion of the University High School campus, formerly the site of a Native American Tongva village.
San Vicente Boulevard is considered the "Main Street" of Brentwood and is divided by a wide median on which stand many large and attractively sculpted coral trees. This green belt replaced a derelict Pacific Electric trolly track, its trees evolving into a City of Los Angeles Historic-Cultural Monument. Brentwood boosters have adopted a coral tree silhouette as a de facto community logo. Intersecting Bundy Drive is lined with extremely tall date palms.