Waters Dewees Roberts was born around 1841 in Pennsylvania to Leonard and Rachel Roberts. His father was a farmer who owned $20,000 of real estate and $4,000 of personal property in 1860. He grew up and attended school in Chester County, Pennsylvania. He enlisted in the Union army on April 20, 1861, and mustered in as a private in Company C of the 4th Pennsylvania Infantry later that day.
The regiment performed garrison duty around Washington, D.C., and the men mustered out on July 27, 1861. He enlisted again on August 19, 1861, and mustered in as a 1st lieutenant in Company B of the 11th Pennsylvania Cavalry. He was promoted to captain on October 1, 1862. He was wounded at Reams’ Station, Virginia, on June 29, 1864, and he died outside Petersburg, Virginia, on July 9, 1864.