Alexander and James Campbell, born and raised in Scotland, immigrated to the United States as teenagers in the 1850s and settled in vastly different regions of the country - Alexander in New York City and James in Charleston, South Carolina. When the American Civil War broke out in 1861, Alexander and James opted to fight for their adopted states and causes: Alexander enlisted in the 79th New York "Highlanders" and James in the 1st South Carolina ("Charleston") Battalion.

"Him on the One Side and Me on the Other" tells the remarkable story of these two brothers divided by the Civil War. Through their wartime letters to family and to each other, the brothers expose the deep fractures in American society caused by the most destructive war in this country's history.

In the most dramatic moment in this story of the brothers' wartime experiences, the letters reveal a near-reunion on the battlefield of Secessionville, South Carolina, on June 16, 1862. There Alexander was part of the Union force that assaulted Tower Battery, a fort inhabited by James and his Confederate comrades.