Statistics for occurrence #1 of “Ohio” in entry jefferson-fort of Harper's Encyclopedia of United States History:

...tion of a station on the Mississippi River between the mouth of the Ohio and the parallel of 36° 30′; and in the spring of 1780 Clarke chose a strong position 5 miles below the mouth of the Ohio , whereon he built Fort Jefferson. Here the Americans planted their first sentinel to watch over the freedom of the navigation of the Father of waters.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
† Ohio (United States) 1,611 200 1 0 0 user votes
Ohio (Ohio, United States) 4,328 891 10 1 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.