Johnston Livingston de Peyster (June 14, 1846 – May 27, 1903) was a soldier in the Union Army during the American Civil War and later a member of the New York State Assembly from Dutchess County, New York. The son of a wealthy old Dutchess County family, de Peyster joined the Union Army at the age of eighteen. He saw service in the eastern theater, and is best remembered for raising the first Union flag over the Confederate capitol of Richmond, Virginia, after its fall in 1865.