The John M. Sell Civil War Collection consists primarily of letters written by John Sell to his parents and brother William during his service in the American Civil War. In these letters Sell describes his various locations, including training at Camp Wright in Oakmont, Pennsylvania in June of 1861. He also wrote about the 83rd Regiment of the Pennsylvania Volunteers, with whom he was stationed at Camp Hall’s Hill by Washington D.C. in November and December 1861, and his regiment's movement to Yorktown in April of 1862, the Potomac in March of 1863, and other locations. He tells of his participation in the Battle at Gaine's Mill and the Battle of Antietam, lists the number of deaths experienced in various firefights, comments on the health and morale of his regiment, describes the actions and death of his superior officer Colonel McLane, and relates the various weather conditions which he and his regiment encountered. The collection  also includes one letter written to his brother Charles, and correspondence between his sister, Sarah, and William H. Edmont, who details Sell's injury on the battlefield at Gettysburg, the amputation of his leg, and his subsequent death. In addition to correspondence, the collection includes family photographs, cartes de visite of military personnel, a metal canteen, and a copy of A.M. Judson's History of the Eighty-Third Regiment Pennsylvania Volunteers, Erie, PA, B.F.H. Lynn, [1865].