4th Regiment, Tennessee Mounted Infantry (Union)
The 4th Regiment, Tennessee Mounted Infantry was organized at large in Tennessee September 1, 1864. They mustered out August 25, 1865. 
For more information on the history of this unit, see:
- The Civil War Archive section, 4th Regiment Mounted Infantry, (accessed 30 March 2012).
Companies in this Regiment with the Counties of Origin
Men often enlisted in a company recruited in the counties where they lived though not always. After many battles, companies might be combined because so many men were killed or wounded. However if you are unsure which company your ancestor was in, try the company recruited in his county first.
- Company A - Men mostly from Bedford County.
- Company B - Men from various West Tennessee Counties.
- Company C - Men from Bedford and Rutherford Counties.
- Company D -
- Company E - Men from DeKalb County.
- Company F - Men from DeKalb County.
- Company G - Men from Wilson, DeKalb and Smith Counties.
- Company H - Men mostly from Wilson County
- Company I - Men from Bedford and Giles Counties.
- Company K - Men from Smith, DeKalb, and Overton Counties. 
- Beginning United States Civil War Research gives steps for finding information about a Civil War soldier or sailor. It covers the major records that should be used. Additional records are described in 'Tennessee in the Civil War' and 'United States Civil War, 1861 to 1865' (see below).
- National Park Service, The Civil War Soldiers and Sailors System, is searchable by soldier's name and state. It contains basic facts about soldiers on both sides of the Civil War, a list of regiments, descriptions of significant battles, sources of the information, and suggestions for where to find additional information.
- Tennessee in the Civil War describes many Confederate and Union sources, specifically for Tennessee, and how to find them.. These include compiled service records, pension records, rosters, cemetery records, Internet databases, published books, etc.
- United States Civil War, 1861 to 1865 describes and explains United States and Confederate States records, rather than state records, and how to find them. These include veterans’ censuses, compiled service records, pension records, rosters, cemetery records, Internet databases, published books, etc.
- Wright, General Marcus J., Tennessee in the War 1861-1865, (Ambrose Lee Publishing Company, Williamsbridge, New York City, 1908), Online book at Internet Archive. Roster of the volunteer force in the United States army from Tennessee. Roster of officers is given as it stood on the day of the muster out. Infantry - The Fourth Mounted Regiment begins on page 184.
- Tennesseans in the Civil War, 4th Tennessee Mounted Infantry Regiment, USA, (accessed 10 November 2011) includes histories for most of the military units of Tennessee.
- Federal Military Rosters, 4th Mounted Infantry Regiment, Company K, (accessed 4 Jan 2012).
- TNGenes Genealogy,4th Tennessee Mounted Infantry Regiment, USA, Roster, (accessed 4 Jan 2012). Alphabetical Roster.