20th Regiment, Ohio Infantry
The 20th Regiment, Ohio Infantry mustered in August 19 to September 21, 1861 at Columbus, Ohio. They were mustered out July 18, 1865 at Louisville, Kentucky. 
For more information on the history of 20th Ohio Infantry see the following:
- Larry Stevens' Ohio in the Civil War, 20th Ohio Infantry
- The Civil War Archive section, 20th Regiment Infantry (3 years), (accessed 29 August 2012).
- The wikipedia article, 20th Ohio Infantry (accessed 12 October 2011)
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 - Many men from Morrow County
Company B - Many men from Fayette County
Company H - Many men from Trumbull and Mahoning Counties
Company K -
A county listing from Steve Ward's Buckeyes All , Part II Revised, is given on Larry Stevens' Ohio in the Civil War web page, 20th Ohio Infantry .
- Beginning United States Civil War Research gives steps for finding information about a Civil War soldier. It covers the major records that should be used. Additional records are described in ‘Ohio 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.
- Ohio in the Civil War describes many Confederate and Union sources, specifically for Ohio, 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.
- Wood, David W. History of the 20th O. V. V. I. Regiment : and proceedings of the first reunion at Mt. Vernon, Ohio, April 6, 1876. (Columbus, Ohio: Paul and Thrall, 1876). This book has a list of those who died while in service on pages 10 to 13. Internet Archive. Also on microfiche, (Bethesda, Maryland : University Publications of America, c1993) FHL Fiche 6118170
- National Park Service, The Civil War Soldiers and Sailors System, (accessed 6 December 2010).
- A J Baughman, History of Morrow County Ohio, (Chicago-New York: The Lewis Publishing Comopany, 1911), page 133. - Internet Archives
- fckLRHistory of Fayette County, Ohio page 180
-  History of trumbull and Mahoning Counties page 126