Statistics for occurrence #1 of “Salm” in chapter 5.18 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.:

...Blenker's regiments were sent forward to the first attack. In the picture Brigadier-General Louis Blenker is standing, with his hand on his belt, before the door. At his left is Prince Felix Salm- Salm , a Prussian military officer, who joined the Federal army as a colonel of volunteers. At the right of Blenker is General Stahel, who led the advance of the Federal left at Cross Keys.
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Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Felix Salm 6 3 2 1 0 user votes
Felix Prince Salm 50 0 4 0 0 user votes
Salm 16 0 0 0 0 user votes
Salm Salm 6 0 6 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.