The collection consists primarily of intrafamily correspondence, the largest percentage of which is the incoming and outgoing correspondence (1857-1906) of Elizabeth Chester Fisk. The collection also contains correspondence (1859-1905) of Robert Fisk including letters from Montana Territorial Secretary James E. Callaway and Governor Benjamin F. Potts; the Civil War letters (1862-1865) of Robert and Van Hayden Fisk; letters (1870-1891) between Robert and Lizzie Fisk's children (Asa, Florence, Grace, James K., and Robert) and Elizabeth's mother, Mrs. Isaac Chester; and a photocopy of a letter (1864) to James L. Fisk from the Secretary of War, appointing him to lead an expedition via Fort Benton. Also included are diaries (1864-1873) written by Andrew J. Fisk, chronicling the Fisk expeditions (see also Microfilm 81 for 1864-1873 diaries), and photocopies of writings (1858-1860) by James Liberty Fisk.