Statistics for occurrence #1 of “Mexico” in chapter 3 of James D. Porter, Confederate Military History, a library of Confederate States Military History: Volume 7.1, Tennessee:

...th distinction. He was an officer of the United States army who had resigned as captain of mounted rifles, and offered his sword to his native State of Tennessee. He was a veteran of the war with Mexico , and was brevetted for gallantry at Cerro Gordo. Colonel Jackson was afterward brigadier-general, and a prominent commander of a cavalry division.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Mexico (Mexico, Mexico) 8,518 14 0 0 0 user votes
Mexico (Mexico) 1,918 0 0 0 0 user votes
Mexico (New York, United States) 45 0 1 0 0 user votes
Mexico (Indiana, United States) 8 0 0 0 0 user votes
Mexico (Kentucky, United States) 0 0 0 0 0 user votes
Mexico (Maine, United States) 0 0 0 0 0 user votes
Mexico (Maryland, United States) 0 0 0 0 0 user votes
Mexico (Ohio, United States) 0 0 0 0 0 user votes
Mexico (Ohio, United States) 0 0 0 0 0 user votes
Mexico (Pennsylvania, United States) 0 0 0 0 0 user votes
Mexico (Pennsylvania, United States) 0 0 0 0 0 user votes
Mexico (South Carolina, 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.