Statistics for occurrence #1 of “Rapidan” in chapter 21, page 390 of Maj. Jed. Hotchkiss, Confederate Military History, a library of Confederate States Military History: Volume 3, Virginia:

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Rapidan , to the Rappahannock at the mouth of Mineral Spring run, a line nearly six miles in length. Lee rode in the midst of his line of battle as his men pressed forward in pursuit, pouring volley after...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Rapidan (Virginia, United States) 580 8 4 0 0 user votes
Rapidan (Louisiana, United States) 2 0 0 0 0 user votes
Rapidan (Minnesota, 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.