Statistics for occurrence #1 of “Little Missouri River” in chapter 21 of Frederick H. Dyer, Compendium of the War of the Rebellion: Regimental Histories:

...e 5-July 1. Pursuit of Indians to the Bad Lands July 5-28. Battle of Tah kah a kuty or Killdeer Mountain July 28. Passage of the Bad Lands August 3-18. Action at Two Hills, Bad Lands, Little Missouri River , August 8-9. Rescue of Fiske's migrant train September 10-30. Engaged in frontier and patrol duty between Forts Wadsworth, Abercrombie, Ripley and Ridgley, Headquarters at Fort Snelling, till...
Max. Freq. Min. Freq.
Entity Corpus Doc Corpus Doc  
Little Missouri River (Wyoming, United States) 19 14 1 0 0 user votes
Little Missouri River (Arkansas, United States) 46 22 0 0 0 user votes
Little Missouri river (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.