Francis John Shunk was born on October 11, 1832, in Harrisburg, Pennsylvania, to Francis Rawn Shunk and Jane Findlay. His father was a Democratic politician who served as governor of Pennsylvania from 1845 to 1848. His father resigned from office on July 9, 1848, and died of tuberculosis eleven days later. Shunk’s brother was
James Findlay Shunk, a UVA alumnus who served in the Union army during the Civil War.
Shunk enrolled at West Point in the late 1840s and graduated in 1853. He received a commission as a 2nd lieutenant in the Ordnance Department of the United States Army. He was promoted to 1st lieutenant on July 1, 1856, and he also became assistant professor of chemistry at West Point that year. He served throughout the Civil War, earning a promotion to captain on March 3, 1863. He remained in the army after the war, and he was promoted to major on March 7, 1867. He died of disease in Richmond, Virginia, on December 15, 1867.