The Seymour papers contain materials relating primarily to the Civil War service of Col. Isaac G. Seymour (6th Louisiana Infantry) and his son, William J., both residents of New Orleans. The most important items in the collection are the two journals kept by William Seymour describing his experiences in the defense of New Orleans, 1862, and as Assistant Adjutant General in the 1st Louisiana Brigade, Army of Northern Virginia. The first of these "journals" was begun by Col. Isaac Seymour as a manuscript drill manual for his regiment (55 pp.), but it appears to have been taken up by William following Isaac's death. This volume is arranged in four sections and includes a record of William Seymour's experiences from March, 1862 through May, 1864. The second volume is organized in a similar manner, but covers the period from April, 1863 through October, 1864, terminating in the middle of a description of the Battle of Cedar Creek. Both of William's "journals" are post-war memoirs drawn extensively from original diaries and notes, with some polishing and embellishment.
William Seymour's "journals" contain outstanding descriptions of life in the Confederate Army and are one of the premier sources for the Confederate side of the Battle of Forts Jackson and St. Philip. His journals also contain very important accounts for Chancellorsville, 2nd Winchester, Gettysburg (Cemetery Hill), Mine Run, the Wilderness and Spotsylvania (the Bloody Angle), but almost as important are the descriptions of camp life, and the morale and emotions of the troops. Seymour is an observant, critical, and knowledgeable writer who was placed in a position where he had access to information on fairly high level command decisions. Yet while his journal is focused on the military aspects of the war, he includes a number of brief personal sketches of officers and soldiers, and vignettes of life in the army, ranging from accounts of Union soldiers bolstered in their courage by whiskey, to the courage of an officer's wife stopping a deserter and the Knights of the Golden Circle surfacing in Pennsylvania during the Confederate invasion.
The remainder of the collection includes three Civil War-date letters relating to Isaac Seymour, one written from Camp Bienville near Manassas, Va. (1861 September 2), one from the Shenandoah River (1862 May 2), and the third a letter relaying news of Seymour's death at Gaines Mills. The letter of May 1862 is a powerful, despairing one, and includes Isaac Seymour's thoughts on the Confederate loss of New Orleans and severe criticism for Jefferson Davis, a "man of small caliber, with mind perhaps enough, but without those qualities which go to make up the great and good man." At this moment, Seymour reported that he was disappointed in the quality of his officers, and regretted that he had not resigned his commission upon his son's enlistment, and further, he felt that the Confederacy was being held together only tenuously, due solely to the "the righteousness of our cause, and the innate, deep rooted mendicable hatred to the Yankee race." The remainder of the correspondence consists primarily of documents, but includes an interesting Seminole War letter of Isaac to Eulalia Whitlock and a letter from "Sister Régis" to Isaac, as editor of the New Orleans Bulletin, begging the aid of the press on behalf of the Female Orphan Asylum.