Cincinnati native William Haines Lytle volunteered for service in the Mexican War in late 1847. A pro-states' rights Democrat with strong family ties to Kentucky, he nevertheless chose to protect and defend the Union upon the outbreak of the Civil War.

Lytle's Mexican War service primarily consisted of garrison duty, but during the Civil War he became known for his courage under fire and his devotion to his troops. He saw combat at Carnifex Ferry and Perryville, and was killed at Chickamauga while leading a valiant charge to stop Confederate troops storming through an opening in Union lines.His letters detail the ferocity of action on the western front and offer a glimpse of the interaction between Union officers and Southern civilians in the border states.