Brooks was born in Saginaw, Michigan, USA, in 1870. His mother died soon after his birth, and he was raised partly by his maternal grandmother in Gloucester, Massachusetts. Brooks took a BA and MA in Fine Arts at Harvard, and also studied at MIT's School of Architecture and Planning in the early 1890s. He later became a Professor of Art at Indiana State University, where he met his wife, Ruth Bryce Steele. He married Ruth in 1910, then in 1922 they moved to Pennsylvania where he took up a post as Professor of Fine Arts at Swarthmore College.
On his retirement in 1937, they moved back to Gloucester, Massachusetts, where they remained until his death in December 1963, aged 94. Their archives are held at the Cape Ann Museum in Massachusetts.