Born in Jamestown, New York, Underwood studied at the Art Students League and the Academy of Julian in Paris in 1896 with J. P. Laurens, Constant and Bouguereau.

He returned to America around 1901/02 to work illustrating for postcards, literary works, and magazines, including World magazine and over 40 covers for the Saturday Evening Post World.

Many of his paintings were romantically influenced, showing courting scenes from over the fence line to stealing a kiss over a chessboard.
Underwood was a member of the Society of Illustrators in New York City in 1910 and was on staff of the New York Press.