Statistics for occurrence #1 of “Gettysburg” in chapter 3.9, page 147 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 1: The Opening Battles.:

... stands General J. B. Sanborn with Lieutenant Sanders (mustering officer) on his right hand, and on Sanders' right is the Honorable Morton S. Wilkinson. Colvill, as Colonel, led the regiment in its Gettysburg charge.
...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Gettysburg (Pennsylvania, United States) 7,452 38 1,368 0 0 user votes
Gettysburg (South Carolina, United States) 0 0 0 0 0 user votes
Gettysburg (South Dakota, 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.