[1] Carnahan's regiment served as part of Major General John C. Fremont's campaign to re-capture Springfield, Missouri, from Confederate forces at the First Battle of Springfield.
When the Union Army arrived in Springfield, only thirty families remained.
[2] In December 1861, his regiment became part of the Army of the Southwest led by Brigadier General Samuel Ryan Curtis.
[4] On January 13, 1866, President Andrew Johnson nominated Carnahan for appointment to the grade of brevet brigadier general of volunteers, to rank from October 28, 1865, and the United States Senate confirmed the appointment on March 12, 1866.
[5] Robert H. Carnahan died on June 14, 1913, at Danville, Illinois.