Statistics for occurrence #1 of “Maryland” in chapter 9 of Brigadier-General Ellison Capers, Confederate Military History, a library of Confederate States Military History: Volume 5, South Carolina:

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The Maryland campaign the South Mountain battles capture of Harper's Ferry battles of Sharpsburg and Shepherdstown. General Lee marched his victorious army from the plains and hills of Manassas to Leesburg...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Maryland (Maryland, United States) 18,573 48 3 0 0 user votes
Maryland (Illinois, United States) 0 0 0 0 0 user votes
Maryland (Liberia) 0 0 0 0 0 user votes
Maryland (Louisiana, United States) 0 0 0 0 0 user votes
Maryland (Louisiana, United States) 0 0 0 0 0 user votes
Maryland (Louisiana, United States) 0 0 0 0 0 user votes
Maryland (New Jersey, United States) 0 0 0 0 0 user votes
Maryland (New York, 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.