This diary/memoir concerns Sneden's service in the 40th New York Infantry Regiment and as a topographical engineer in the III Corps, Army of the Potomac. The majority chronicles his wartime experience in Washington, D.C., and Virginia from the summer of 1861 until the fall of 1863, including his enlistment, duties, and capture by John Singleton Mosby in November 1863. His life as a prisoner of war is chronicled in great detail, including his seven-month imprisonment at Andersonville Prison, ending with his exchange in December 1864 and discharge in January 1865. Sneden includes descriptions of campaigns and battles in which he did not participate, including the war in the western theater. Of particular note are the watercolor drawings and maps rendered by Sneden that are scattered throughout the volumes to illustrate his narrative. Also included are numerous pieces of ephemera, the majority of which are bank notes (federal, Confederate, and state) accompanied by notes by Sneden on their significance to his story. Vol. I of the diary covers the period from the bombardment of Fort Sumter in April 1861 to the eve of the battle of Williamsburg on 5 May 1862. Vol. 3 covers the period from the battle of Savage's Station, Va., on 29 June 1862 through Jeb Stuart's cavalry raid on Chambersburg, Pa., in early October 1862. Vol. 4 covers the period from the eve of the Fredericksburg Campaign in October 1862 to the battle of Rappahannock Station, Va., in November 1863. Vol. 5 covers the period from the Mine Run Campaign of November 1863 to the trial and execution of the Andersonville "Raiders" in July 1864. Vol. 6 covers the period from Sneden's departure from Andersonville Prison in September 1864 to the grand reviews of the U.S. armies in Washington, D.C., in late May 1865. Vol. 7 consists of Sneden's illustrated and annotated copy of Thomas Prentice Kettell's History of the Great Rebellion (1865).
