Contains seventy-one letters from Proudfit, primarily to his wife Emelie and sister Julia, during Proudfit's service in the Wisconsin Twelfth Voluntary Infantry Regiment. Included are three letters to Proudfit from his wife, one from his sister Julia, and one from his sister Julia's husband, "D. Worthington." Also included are a printed list of officers, companies, and Company B officers and privates in the Twelfth Regiment, and a handwritten 1862 order concerning Proudfit from Col. George E. Bryant. [Spine and cover embossing: "Civil War Letters, 1861-1865."]