The James Stewart diary contains 106 pages of entries, covering September 7, 1861-April 6, 1863. Laid into the volume are an 1864 letter, a 1917 pamphlet entitled "Who Is a Christian?" and an undated newspaper clipping.
In his earliest entries, Stewart described his enlistment in the 12th Iowa Infantry, camp life, and his regiment's travels through Iowa, Missouri, and Tennessee by boat and rail. He dated entries using the Quaker system, although no other references to the Quaker religion appear in the diary.
In February 1862, Stewart wrote detailed descriptions of engagements at Fort Henry and Fort Donelson. Regarding the former, he discussed the regiment's movements, the capture of property and prisoners, and the presence of gunboats (pp. 14-15). On February 12-16, he gave an account of the Battle of Fort Donelson, describing his proximity to the Confederate soldiers, a successful charge (p. 17: "we changed up through the fallen timber to the works & took them by storm & held them till night"), and his relief when the Confederates surrendered and he saw "the white flag coming to meet us" (p. 18).
On April 18, 1862, Stewart wrote an 8-page account of the Battle of Shiloh, including his capture after being "penned in" by Confederates (p. 29). He followed this with approximately 50 pages of entries concerning his imprisonment from April to October 1862. He described traveling through the towns of Corinth, Memphis, Jackson, Mobile, Montgomery, Columbus, and Macon, with 900 fellow prisoners (p. 36). Throughout his time as a prisoner of war, Stewart frequently commented on the quantity and quality of food available; the treatment of prisoners; and his activities in prison camp, including debates with Confederate soldiers (p. 43), interactions with German guards (p. 52), musical performances by slaves (p. 53), and the arrival of political prisoners who "would not take up arms against their country" (p. 62). He found conditions overcrowded and "unhealthy" (p. 41), but often remarked about his good care, particularly earlier in his imprisonment. By August, he observed that prisoners died at a rate of five to six per day (p. 72). After his release from prison, Stewart wrote fewer than 20 pages, in which he described his journey back to St. Louis, the death of his brother on March 6, 1863 (p. 104), and the receipt of new muskets (p. 106).
Also included in the volume is a letter from Captain Charles L. Sumbardo to John D. Stewart, of the 12th Iowa Infantry, offering sympathy at the death of James Stewart and providing remarks on Stewart's character. This is accompanied by a newspaper clipping about the double wedding of sisters Rachel and Hannah Stewart and a pamphlet entitled "Who Is Christian," prepared by Sarah Griscom.