In 1914, a group of citizens in the village of Brentwood took a set of grievances to the Baldwin Township Board of Commissioners, regarding the lack of sidewalks, sewers, fire protection, police, and a school house.

Upon further disregard of these necessities from the township, a group of men from the village held a meeting on January 27, 1915, to discuss secession.

On November 6, 1915, the Quarter Sessions Court of Allegheny County decreed that Brentwood was officially seceded from Baldwin Township.

On Labor Day, 1928, the borough celebrated the official opening of the park, pool, and paving of Brownsville Road.

He was involved with a number of historic government initiatives and large civic development projects, being both local and regional in scope.

A Hall of Fame NFL linebacker, Joe Schmidt played for Brentwood High School.

[4] According to the United States Census Bureau, the borough has a total area of 1.5 square miles (3.9 km2), all land.

Due to its position between the Great Lakes and the windward side of the Allegheny Mountains, Brentwood, along with the rest of the region, receives plentiful precipitation which supports lush vegetation.

That wind carries moist air from the lake, producing clouds and heavy snow squalls.

Brentwood has three borders, including Baldwin to the east and northeast, Whitehall to the south and west, and the Pittsburgh neighborhood of Carrick to the northwest.

Brownsville Road follows the route of a pre-Columbian era Native American Indian trail and footpaths connecting Redstone Old Fort with the "forks of the Ohio", a distance of 26 miles (42 km).

It later became the road connecting Pittsburgh with Brownsville, Pennsylvania, and from there via Nemacolin's Path to Virginia and points further east.

The hotel was then turned into a restaurant and bar until the property was sold and demolished in November 2006, as it was never officially recognized as a historic landmark.

The John F. Slater Funeral Home, formerly the White Hall Tavern, was another important place in Brentwood's history.

The White Hall Tavern was just a short walk to the race track which was once on the site of the South Hills Country Club, which is why many people from the city stopped here for relaxation.

The Brentwood High School Spartans play football, soccer, baseball, and softball, in the local park.

The project was spearheaded by the Brentwood Park Initiative, the independent committee helping to raise funds and community awareness.

The renovations included new turf to replace the grass field at Brentwood Stadium; a quarter-mile rubber track; an in-line dek hockey rink; new basketball and tennis courts; and energy-efficient lighting.

The high school was newly built in 1932 adjacent to the current Brentwood Park; an addition was constructed in 1939 because of the increase in population, and once again in 1959.

The district also built a new academic wing to the front of the 1939 building, and a second gymnasium was placed on the demolished third and fourth floors of the 1972 addition.

St. Sylvester served as Brentwood's parochial elementary school, teaching children from preschool to 8th grade.