Robert Knox Sneden (1832–1918) was born in Nova Scotia and later moved to New York City, where, in the summer of 1861, he enlisted in the 40th New York Infantry Regiment. Sneden served with the Army of the Potomac in Virginia during the Peninsula Campaign and the Seven Days' Battles and in Washington, D.C., as a topographical engineer on the staff of Maj. Gen. Samuel P. Heintzelman.1861-1865