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Sutlers of the Civil War By Claire Prechtel-Kluskens
Also found the following.
Civil War Sutler's Clerk Archive, Letters Written by Frederick P. Ranney, 40th New York Volunteer Infantry, 1861-1867 | Cowan's Auction House: The Midwest's Most Trusted Auction House / Antiques / Fine Art / Art Appraisals (cowanauctions.com)
Dear Ms. Jacobs,
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We searched the National Archives Catalog and located 91 series and 772 file units related to sutlers in the 1860s that may be of interest to you. Most of the records are invoices, registers, claims, letters, and similar records, and there may be some information related to your research amongst them. Most of the records have not been digitized. You may contact the reference unit listed in each Catalog entry for assistance with these records. For example, many of the records are in the custody of the National Archives at Washington, D.C. - Textual Reference (RDT1), and you may email them at email@example.com with any questions you might have about those records.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1 or other NARA reference units. We apologize for this inconvenience and appreciate your understanding and patience.
In addition, we located 56 references to "Sutler" on the Social Networks and Archival Context (SNAC) website that may be of interest to you. The “Resources” tab in each entry lists collections that relate to each individual.
We hope this information is helpful, and best of luck with your research!