John B . Bachelder John Badger Bachelder ( September 29 , 1825 – December 22 , 1894 ) was a portrait and landscape painter , lithographer , and photographer , but best known as the preeminent 19th - century historian of the Battle of Gettysburg in the American Civil War . He was a dominant factor in the preservation and memorialization of the Gettysburg Battlefield in the latter part of the century . Early life . Bachelder was born in Gilmanton , New Hampshire . He was educated at Captain Alden Partridge ' s Military School in Pembroke and then at an academy in Gilmanton . He eventually moved to Reading , Pennsylvania , to work at a school that would later become known as the Pennsylvania Military Institute , becoming its principal in 1851 . He became involved with the Pennsylvania state militia and was appointed a colonel in 1852 , a title that was associated with him the rest of his life . In 1853 Bachelder returned to New Hampshire , where he married Elizabeth Barber Stevens , and began his career as an artist . Elizabeth was a niece to Gen . politician . From his brief association with military topics , he retained a lifelong interest in them , and when the Civil War began in 1861 , he was already collecting notes on Bunker Hill , planning to paint an accurate rendition of the battle . When he realized that reliable materials were hard to locate , he decided to accompany the Union Army of the Potomac in hopes of being present at a decisive battle . There , he would be able to examine the topography of the battlefield , interview participants , and publish a written and illustrated history of the battle . Bachelder was a welcome accompaniment to the Army , as evidenced by a number of letters in his personal papers from prominent generals who complimented him on his work . For example , Brig . Gen . John C . Caldwell wrote in early 1863 , " At Fair Oaks , Virginia , I frequently met Mr . Bachelder , at that time making sketches of various phases of the Battle of Seven Pines and Fair Oaks . Several of the sketches were shown to me , and I think them " by far " the most accurate of any I have ever seen . " Gettysburg . Bachelder ' s most noted work , which would occupy a good portion of the remainder of his life , was after the Battle of Gettysburg , July 1 – 3 , 1863 . He studied the terrain via horseback and drew an isometric map of the battlefield . He visited field hospitals , interviewed wounded soldiers of both armies , and determined the position on his map of every unit engaged in the battle . That fall he published a panoramic view of Gettysburg . During visits to the Army ' s winter quarters , he claims to have interviewed the commanders of every regiment and battery in the Army of the Potomac . He later organized reunions on the field and accompanied veterans over the terrain and placed wooden stakes into the ground to identify important points of the battle . In 1870 , noted artist James Walker was commissioned by Bachelder to paint an account of Pickett ' s Charge , entitled " The Repulse of Longstreet ' s Assault at the Battle of Gettysburg , " a massive work that measured 7 . 5 by 20 feet . Bachelder wrote an accompanying guidebook and toured widely with the canvas , lecturing across the United States . In 1873 , he published a guidebook to the battle , which was well received by the public . Bachelder ' s contribution to Gettysburg was more than artistic . From 1883 to 1887 , he served in the position as Superintendent of Tablets and Legends for the Gettysburg Battlefield Memorial Association , and is probably responsible more than any man for the placement of monuments and battlefield markers , both Union and Confederate . He coined the phrase " Copse of Trees " and invented the concept of a " High Water Mark of the Confederacy " at which the famous Pickett ' s Charge peaked . All but a few monuments on the battlefield bear some of his influence . In 1880 , President Rutherford B . Hayes signed into law a bill that provided $ 50 , 000 to Bachelder to write a detailed history of the battle of Gettysburg . Bachelder based his manuscript on the Official Records and the interviews he had done , but he has been criticized by some historians because his personal interviews , which would be considered more accurate than reports compiled years after the event , affected only about 10 % of the 2 , 550 pages that he sent to Washington in October 1886 . Southern historians also complained that he chose to interview very few Confederate officers . Bachelder ' s activities at Gettysburg were described in detail by Senator Wade Hampton of South Carolina on March 17 , 1880 , in a report to the Senate from its Military Affairs Committee : Death . Bachelder died of pneumonia in Hyde Park , Massachusetts , in 1894 . His body was then transported the 79 miles to be buried alongside his only child , Charlotte who died at 13 , in a small family cemetery , on Stevens Hill Road in Nottingham , New Hampshire , close to the family home . His widow , Elizabeth , died in 1914 and was interred along side her husband and daughter .