The unit was originally organized in the Missouri State Guard early in 1862 as McCulloch's Cavalry Battalion, Second Brigade, then was transferred to the Confederate service with four other companies as the 4th Battalion Missouri Cavalry. Company E's commander was Mexican War veteran Captain William H. Couzens.
In July of 1862, the battalion was increased to regimental strength. It held the distinction of being the only Missouri cavalry unit to serve mounted while in the Confederate service. Co. E fought in Mississippi, Tennessee, and Alabama under Generals Frank C. Armstrong, James R. Chalmers, and Nathan Bedford Forrest. The regiment surrendered May 5, 1865 in Citronelle, AL. "Boys of the Best Families in the State" is a meticulously detailed roster of all the men of Co. E, drawn from National Archives and Records Administration microfilm records, period newspaper accounts, soldiers' letters, local histories and court records, and interviews with soldiers' descendents. Included is a day to day record of events for Co. E, also a complete bibliography and index.