Francis J. Herron attended the Western University of Pennsylvania, but left at the age of sixteen without completing his degree to become a bank clerk.

In August, Herron was promoted to lieutenant colonel of the 9th Iowa Volunteer Regiment and fought in the battle of Pea Ridge, where he was wounded and taken prisoner, but exchanged shortly afterwards.

Herron's and Blunt's combined command engaged Thomas C. Hindman in the battle of Prairie Grove and forced the Confederates to abandon western Arkansas.

During the Siege of Vicksburg, Herron's division was placed on the extreme left flank of the Union lines.

During this time, he provided aid to Mexican President Benito Juárez and prevented French troops of Emperor Maximilian from establishing themselves along the Rio Grande.

He was a member of the Grand Army of the Republic and the Military Order of the Loyal Legion of the United States[4] The commonly accepted story that Herron died in poverty is likely false, as the "tenement" in which he lived at the time of his death was in a fashionable neighborhood and well-appointed.