42nd Regiment, Ohio Infantry
The 42nd Regiment, Ohio Infantry mustered in September to November, 1861 at Camp Chase, Columbus, Ohio. They were mustered out as follows: Companies "A," "B," "C" and "D" mustered out September 30, 1864. Companies "E" and "F" mustered out November 25, 1864, and Companies "G," "H," "I" and "K" mustered out December 2, 1864. 
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 A - Many students from the Hiram Eclectic Institute, Hiram, Mantua, Portage County.
Company B - Many men from Medina and Portage Counties.
Company C - Many men from Ashland County (Color Company) and from the townships of Sullivan, Montgomery, Perry, Orange, Clear Creek, Troy and Milton.
Company D - Many men from Mt. Ephraim, Noble County.
Company E - Many men from Lorain, Medina and Portage Counties.
Company F - Many men from Ashland and Portage Counties.
Company G - Many men from Ellsworth Cadets, Newburgh, Medina County.
Company H - Many men from Ashland College, Ashland County.
Company I - Many men from Champaign, Clarke, Darke, Logan, Miami and Shelby Counties.
Company K - Many men from Logan and Medina Counties.
County listing from Steve Ward's Buckeyes All, Part II Revised, as given on Larry Stevens' web page, 42nd Ohio Infantry. (accessed on April 11, 2011)
National Park Service, The Civil War Soldiers and Sailors System, (accessed 6 December 2010).
- National Park Service, The Civil War Soldiers and Sailors System, (accessed 6 December 2010).