40th Regiment, Ohio Infantry
The 40th Regiment, Ohio Infantry mustered in December 7, 1861 at Camp Chase, Columbus, Ohio. Veterans and Recruits consolidated with 51st Ohio Infantry December 10, 1864. 
For more information on the history of 40th Ohio Infantry see the following:
- The Civil War Archive section, 40th Regiment Infantry, (accessed 30 August 2012).
- Larry Stevens' Ohio in the Civil War, 40th Ohio Infantry
- The wikipedia article, 40th Ohio Infantry (accessed 22 November 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.
Companies by County:
Company F - See Roster.
Company G - SeeRoster.
Company H - See Roster.
Company I - See Roster.
Company K - See Roster.
A county listing from Steve Ward's Buckeyes All, Part II Revised, is given on Larry Stevens' Ohio in the Civil War web page, 40th 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.
- Beach, John N.History of the Fortieth Ohio Volunter Infantry. (Bethesda, Maryland : University Publications of America, c1993) FHL Fiche 6118191 and (Columbus, Ohio : Ohio Historical Society, 1988) FHL Film 1688766 Item 3
- National Park Service, The Civil War Soldiers and Sailors System, (accessed 6 December 2010).
- John N. Beach, History of the Fortieth Ohio Volunteer Infantry, (London, Ohio: Shepherd and Craig, 1884), p. 10. Internet Archive. FHL film 1688766 Item 3
- The History of Union County, Ohio, containing a history of the county its townships, towns ... military record, (Chicago: W.H. Beers: 1883), part IV, page 446. Digital version: Internet Archive, accessed 4 December 2012.