Born in Charles County, Maryland, in 1872, Simmons came as a child came to Washington, D.C., where he would later establish his career in architecture.
[1] He received his architecture degree at the University of Maryland, and continued his study at MIT.
[3] In 1902, the Evening Star described Simmons as "an architect who has added to the beauty and growth of this city.
"[1][4] He established himself as an extremely prolific architect, ultimately designing more than 280 buildings in the city.
[5] Although he never studied at the École des Beaux-Arts, Simmons became a student of the Beaux Arts tradition and the City Beautiful Movement.