John Gross Barnard (May 19, 1815 – May 14, 1882) was a career engineer officer in the U.S. Army, serving in the Mexican–American War, as the superintendent of the United States Military Academy and as a general in the Union Army during the American Civil War. He served as Chief Engineer of the Army of the Potomac, 1861 to 1862, Chief Engineer of the Department of Washington from 1861 to 1864, and as Chief Engineer of the armies in the field from 1864 to 1865. He also was a distinguished scientist, engineer, mathematician, historian and author.
Early life and career
John G. Barnard was born into a large and gifted family in Sheffield, Massachusetts. His brother, Frederick Augustus Porter Barnard was a longtime educator and president of Columbia University and namesake of Barnard College in New York City. Both John and Frederick, as well as most members of their family, suffered from a hereditary form of deafness which intensified in later years. In early life, when stationed in New Orleans, Barnard married Jane Elizabeth Brand, of Maryland, with whom he had four children. In 1860, he married Anna E. Hall of Harford County, Maryland, with whom he had three children.
In 1833, at the age of 18, Barnard graduated from the United States Military Academy at West Point, New York, second in a class of forty-three cadets. As one of the top graduates of his class, he was posted as a Second Lieutenant in the United States Army Corps of Engineers, embarking on a 48-year career in that branch.
Barnard's first assignment after being commissioned was as an assistant to Colonel Joseph G. Totten in constructing Fort Adams in Newport, Rhode Island, from 1833 to 1834. Totten was the foremost American military engineer of his day and served as Chief Engineer of the Army for much of Barnard's career. There the two formed a close friendship as evidenced by Barnard's extensive eulogy of Totten which was published in 1866.
Throughout his career, Barnard served on many garrison and fortification details, most notably participating in the construction of coastal defenses at Fort Columbus/Fort Jay, Fort Hamilton and Fort Wadsworth in New York City, New Orleans, Pensacola, Mobile, Fort Livingston, Louisiana, Fort Jackson, Louisiana, Fort St. Philip, Louisiana and on the Pacific Coast at San Francisco. During the Mexican–American War, he headed the construction of American defenses at the captured Mexican port of Tampico, ensuring that city's safety as a vital supply line for American forces advancing on Mexico City. He also worked on the survey of Mexican–American War battlefields. and as chief engineer for the Exploration and Survey of the projected Tehuantepec Railroad in Mexico, in 1850–1851.
From May 31, 1855, through September 8, 1856, Barnard served as the Superintendent of the United States Military Academy, succeeding Robert E. Lee. He then returned to work on coastal defenses, especially in the New York and New Jersey area. During a leave of absence, he studied construction projects in Europe.
Civil War
Soon after the outbreak of the Civil War, U.S. Army commander Major General and Brevet Lieutenant General Winfield Scott, bearing in mind Barnard's success at defending his Tampico-based supply lines during the Mexican–American War, assigned then Major Barnard to the Department of Washington. This was the Union Army unit in charge of defending Washington, D.C., the capital of the United States. On April 28, 1861, Colonel Joseph K. Mansfield, the department commander, a former engineer himself, attached Barnard to his headquarters as chief engineer.
When the Union Army moved into Northern Virginia on May 24, 1861, Barnard oversaw the erection of fortifications on the Arlington hills. He also accompanied the Army to Manassas in July 1861 and was present at the Union defeat at the First Battle of Bull Run (Manassas). Between June 1861 and September 1861, Barnard also served on the U.S. Navy's Blockade Strategy Board. Major General George B. McClellan assumed command of the Military Division of the Potomac, the troops around Washington, D.C., on July 23, 1861. On August 15, 1861, McClellan was appointed to the command of the Army and Department of the Potomac, and Barnard became chief engineer of the Military District of Washington. As McClellan formulated his thoughts for fortifications around Washington, D.C., Barnard planned, designed and oversaw their construction.
In Barnard's A Report on the Defenses of Washington, published after the Civil War, he commented on the complexity and ever-changing nature of the project: