Statistics for occurrence #1 of “Rapidan” in chapter 4.14 of Robert Underwood Johnson, Clarence Clough Buell, Battles and Leaders of the Civil War. Volume 4.:

... as lieutenant-general was given to me on the 9th of March, 1864. On the following day I visited General Meade, commanding the Army of the Potomac, at his headquarters, Brandy Station, north of the Rapidan . I had known General Meade slightly in the Mexican war, but had not met him since until this visit. I was a stranger to most of the Army of the Potomac; I might say to all except the officers of ...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Rapidan (Virginia, United States) 580 12 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.