Series 1: Correspondence, 1827-1913, chiefly contains letters written to Siram P. Henkel with correspondents including members of the Koiner/Coiner family of Augusta County, the Miller family of Winchester, and the Rupert family of Augusta County. The correspondents report on family and community news, marriages, health and illnesses, deaths, weather, harvest and planting updates, crop yields, and include fellow merchants requesting advice on the market of certain goods and numerous requests for Dr. Henkel's pills. Of particular interest are the letters written to Siram by his sons Lewis and Luther while serving in the American Civil War. The sons, and Luther in particular, write about camp life and general updates related to the war. In a December 21, 1861 letter to his father, Lewis P. Henkel writes from Winchester and mentions General Stonewall Jackson. He also refers to General Gilbert S. Meem as "Genl. Drunk."

This series also contains correspondence to/from other Henkel family members including Dr. Solomon Henkel, Samuel G. Henkel, Solomon D. Henkel, Maggie Henkel Renalds, Lillian Henkel, and Margaret Koiner Henkel.

The documentary record confirms that Margaret Koiner Henkel's family were enslavers and given the date of much of the correspondence, a portion relates to slavery and enslaved persons. Delia Koiner Overholt wrote to her sister Margaret Henkel on May 28, 1847 relaying the news of their grandfather's death. She goes on to write that "eleven or twelve blacks are to be sold and a great deal of property." In a January 24, 1857 letter to Siram Henkel, Delia Koiner Overholt writes again to describe in detail describes the sale of enslaved persons from her grandfather's estate. A similarly noteworthy letter, dated August 13, 1835, was penned by Siram Henkel to his wife Margaret in which he describes a large "drove" of enslaved persons that passed through the Valley. He describes the scene as follows: "There were eighty-four chained together to one long chain; there were also a great many women and children that were also in company; the whole number of men, women & children was two hundred and forty." There are two original copies of this letter in the collection.

All correspondence addressed to Dr. Solomon Henkel and/or Solomon Henkel P.M. is filed with Solomon Henkel (1777-1847), who was a practicing physician and served as Shenandoah County's first postmaster. A concerted effort was made on behalf of the archivist to not confuse his papers with those of his son Solomon David Henkel (1815-1872).

Much of the correspondence includes envelopes or address leaves. The correspondence is arranged primarily by recipient, but in cases where the recipient is unknown (e.g. non-specific salutations and greetings or lack of return address), the correspondence is filed with miscellaneous correspondence. Some of the letters have non-original annotations on the address leaves relating to content or the correspondents.

Series 2: Personal Papers, 1801-1881, includes miscellaneous papers from the immediate family of Siram Henkel. School papers and writing assignements from Siram and Margaret Henkel's children, Lewis, Samuel, Julia, Martin, and Maggie are included. The documents include a January 17, 1881 essay on politeness written by Maggie Henkel.

The series also includes a manuscript music book penned by Siram's mother, Rebecca Miller Henkel, a grammar copybook belonging to Siram's brother Slyvanus Henkel, and Siram's 1878 plans for his family's new home place at Plains Mill.

Series 3: Financial Files, 1832-1894, contains receipts, ledger pages, and promissory notes. Included in Siram Henkel's financial papers is a form of the estimate and assessment of agricultural products to be taxed by the government of the Confederate States. Of particular interest is Paul P. Henkel's 1844-1872 daybook entitled "Sawmill Book No. 3" documenting the sawmill owned by Solomon Henkel. The daybook records prices for sawing and details sawing activities. Elizabeth Garber Renalds' account book and journal documents egg business and other farming and day-to-day activities while the family was living at the Lincoln Homestead on Linville Creek south of Broadway.

Series 4: Genealogy and Research Files, 1890-2008, is comprised of research material, much of which was used to inform Mildred Renalds Wittig's Henkel – Renalds Connection: with Ancestral Scripts and Collections (2014). Documents include family trees, facsimiles of correspondence and manuscript material not otherwise found in this collection, photographs of Henkel family members and properties including Plains Mill and the Plains School, newspaper clippings, Henkel family reunion materials, and blank postcards. An oversize reproduction of a blank family register printed by Ambrose Henkel & Comp. is included.

Series 5: 2023-0329 Accession, 1864-1923, includes Henkel family correspondence, Renalds family correspondence, and letters written to Ray Renalds while he was admitted to Rockingham Memorial Hospital in 1923 for an undisclosed illness.

School materials were created by Lillian Henkel while a student at the Shenandoah Institute in Dayton and Harry S. Henkel while a student at Dunsmore Business College in Staunton. Coursework created by Ray Renalds while a student at Shenandoah Luthern Institute is included.