This collection of Civil War letters from the pen of Captain John M. Lemmon of the 72nd Ohio Volunteer Infantry fills a void in Civil War scholarship, covering the entire service of one of most highly regarded regiments in the Army of the Tennessee. Lemmon enlisted in 1861 and served with the 72nd Ohio throughout its term of service. Captain Lemmon proved a keen observer of the war and the issues over which it was fought; his record within the regiment was one of an earnest yet modest officer. His letters document the war as it was fought in western Tennessee and northern Mississippi, a theater characterized equally by grand engagements and periods of tedium. From Shiloh to Vicksburg, Brice's Crossroads to Nashville and beyond, Sherman's Praetorian Guards tells the complete story of the 72nd Ohio Volunteer Infantry.