Yes. Brooklyn is a placename. The most famous place named Brooklyn one of the boroughs of New York City that is also known as Kings County, New York.
A proper noun is the name of a person, place, thing, or a title. The word Brooklyn is the name of a place, a proper noun.
The Brooklyn I ever heard of is female. ( Swimsuit Model Brooklyn Decker )
Brooklyn is the name of the Borough and Kings is the name of the county
Brooklyn Beckham's birth name is Brooklyn Joseph Beckham.
Brooklyn Garrison's birth name is Brooklyn Joyce Garrison.
Brooklyn Night's birth name is Natalie Sloan.
Brooklyn was built here because it is a beautiful place!
The Brooklyn Robins
Brooklyn is a place name and proper noun in America. Most famously, it refers to the borough of New York City which comprises Kings County, New York. Although it may have connotations such as diverse, ethnic, immigrant, urban, hipster, etc., it has no specific meaning or definition other than as a place name.
Brooklyn Bordelle's birth name is Brooke Leigh Girden.
Brooklyn Rhodes's birth name is Melanie Nan Donahue.
Brooklyn Keller's birth name is Edwin Allen Keller.