Brook Playground and the adjacent avenue are named for Mill Brook, a stream which once ran through this neighborhood before the area was developed. The stream flowed from Gates Place in the north Bronx, along what is now Webster and Brook Avenues, and into the Bronx Kill, serving as an important boundary in the nineteenth century; it divided the lands of various Bronx estates, including those of the Bathgate and Morris families.
Brook Park is also known locally as Alexander Burger Park. Burger (1873–1932) was born in Lithuania, and immigrated to the United States, settling in the Bronx. He ran an office furniture manufacturing company, Art Steel, Inc., which was one of the first local businesses to racially integrate its workforce. In recognition of his courage and concern for his community, the school across the street, J.H.S. 139, now bears his name. To this day, the Burger family continues to play an active role in the school’s affairs.