Statistics for occurrence #1 of “Illinois” in chapter 15, page 599 of Edward L. Pierce, Memoir and letters of Charles Sumner: volume 3:

...y as a candidate for the Presidency; Minnesota and Oregon had been added to the sisterhood of States, forever destroying the balance between freedom and slavery in the Senate; the memorable debate in Illinois between Douglas and Lincoln had taken place, in
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Illinois (Illinois, United States) 6,200 52 0 0 0 user votes
Illinois (New Mexico, United States) 4 0 0 0 0 user votes
Illinois (Oregon, United States) 2 0 0 0 0 user votes
Illinois (Colorado, United States) 0 0 0 0 0 user votes
Illinois (Illinois, United States) 0 0 0 0 0 user votes
Illinois (New Mexico, 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.