The Hardenbergh family papers is a collection of letters written by various members of Catharine's family between 1858-1866. The letters written by James and Solomon Hardenbergh (b. 1835; d. 7-7-1864), (an older and her youngest brother, respectively) and Charles Stanton, one of Catherine's sons-in-law, reflect on various aspects of military life and the campaigns in which they participated. They also make frequent reference to the diseases which took the lives of many Union soldiers. The letters written by Catharine and her sister, Deborah, provide some insights on the conditions on the homefront during the war.

The collection includes a brief history of the Hardenbergh and Baker families which provides the researcher with an idea of the genealogical relationships between individuals represented. The collection is arranged alphabetically by writer of the letter.

Also included is correspondence detailing Solomon's death, a letter from an Albert Boyce (who was possibly one of Solomon's friends), three documents written by members of the Stanton family, one letter writer by G. W. Gordon (relationship unknown), and one letter signed ER, possibly Catharine's nephew (ER Harmon). The battles which are describe in the collection are Dr. Caine's Farm, Virginia Bayou Teche, Louisiana Port Hudson, Louisiana Sabine City, Louisiana Alexandria.

Civil War related materials (folders 2-9 and the CDVs) have been transcribed, scanned and placed online at http://civilwar.archives.msu.edu/collection/7-1C-13/hardenbergh-family.