Statistics for occurrence #1 of “Pennsylvania” in chapter 15 of Southern Historical Society Papers, Volume 4.:

... side, have written with that laborious painstaking care indicative of intelligent or conscientious historians. To begin, you err in stating that the Army of Northern Virginia in its invasion of Pennsylvania was more powerful than it had ever been before. In numbers it was at its maximum in 1862, when contending with the Army of the Potomac, then commanded by your old chief and my friend, General McCl...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Pennsylvania (Pennsylvania, United States) 12,690 108 2 0 0 user votes

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