Statistics for occurrence #1 of “Ohio” in chapter 3.9 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 1: The Opening Battles.:

...navy was drawn upon and a battalion of marines was included in the Union forces. In addition to the regulars were volunteers from all the New England States, from New York and Pennsylvania and from Ohio , Michigan, and Minnesota, organizations which, in answer to the President's call for troops, had volunteered for three months service. Many were boys in their teens with the fresh glow of youth on ...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Ohio (Ohio, United States) 4,328 20 10 0 0 user votes
Ohio (United States) 1,611 6 1 0 0 user votes
Ohio (Colorado, United States) 12 0 0 0 0 user votes
Ohio (Illinois, United States) 0 0 0 0 0 user votes
Ohio (Missouri, United States) 0 0 0 0 0 user votes
Ohio (New York, United States) 0 0 0 0 0 user votes
Ohio (Texas, United States) 0 0 0 0 0 user votes

† This entity has been selected by the automated classifier as the most likely match in this context. It may or may not be the correct match.