Complex sentence: The highest-ranking officer, Colonel John Todd of the Fayette militia, was in overall command; under him were two lieutenant colonels, Stephen Trigg of Lincoln County and Daniel Boone of Fayette County.
Split into simpler sentences: The highest-ranking officer, Colonel John Todd of Fayette County, was in overall command. Assiting him were two lieutenant colonels, Stephen Trigg of Lincoln County and Daniel Boone of Fayette County.