The James K. P. Sayler Papers, 1857-1943, contain correspondence, writings and speeches, bills, contracts, and other papers related to the life of Sayler, a Confederate soldier during the Civil War and a teacher in East Tennessee.

The bulk of the collection consists of correspondence, including letters written to and by Sayler. In the earlier correspondence, letters from Sayler's cousin Benjamin F. Smith detail the life of a man moving westward in the United States. In an October 15, 1859 letter from Bloomfield, Missouri, Smith notes that "our country is fast increasing though both in population & improvement. The emigration is considerable. Our internal improvements are developing rapidly & Christian reform is progressing unparallell [sic] & uninterrupted." Smith's letters also contain a vast array of information on Missouri's political scene prior to the Civil War. He speaks at length about the gubernatorial race as well as the influence of the Know-Nothing Party and Republicans in the state. In a letter written May 10, 1861, Smith also speaks of unrest in the town, saying that "the citizenry met to organize for our defense."

The correspondence dating after 1861 contains many letters from Sayler and his brother John, both of whom served as Confederate soldiers during the war, to their family in Greeneville. Sayler, who served in the Vicksburg, Mississippi, area, provides descriptions of camp life as well as information on military movement and battles. In a February 6, 1863 letter, Sayler tells his father that he was under fire for three days, during which "the bullets whistled around me almost as thick as hail, but God protected and shielded us from harm."

Also included in the Civil War-era correspondence are letters from Sayler's father John and other family members to the sons. A small number of letters are from Joseph B. Correll, a fellow soldier stationed in East Tennessee. These letters provide information on friends and family members as well as details on military and civilian happenings in Greeneville and throughout East Tennessee.

Post-Civil War, the majority of the letters in the collection are from students and colleagues of Sayler, who served as a teacher in Romeo, Tennessee. Many of these letters include debates on religious interpretation and talks of teachers' salaries and treatment throughout the state.

The final portion of the collection contains writings and other speeches made by Sayler as well as bills, contracts, and other papers. The writings include both fiction (including short stories such as True Love Never Runs Smooth and Lost Ida) and non-fiction (consisting of speeches on education and religion).