In General Jo Shelby’s March (Random House), Anthony Arthur writes of Shelby’s journey into Mexico after the Civil War, which offered him the chance to continue fighting the Union. But just across the border he met with Mexican rebels who were fighting Maximilian, the French-backed emperor of Mexico. Shelby suggested to his men that they join the rebels, but they were in favor of joining the French instead. Shelby relented. The “Iron Brigade” thus began a march to Mexico City to join the French and, among other goals, establish a safe haven for Southerners wanting a new home.

Arthur (who died shortly after he finished the book) gave me far more than I bargained for. He not only carefully paints a complex, driven individual—once unforgiving and later forgiving—he gives you an intimate view into Shelby’s warrior mentality. Arthur also fortifies his story with insightful and fresh snippets from the diaries of a young American woman in Mexico, Sara Yorke. We get poetry from the troops, as well as letters and testimonials from Southerners emigrating to Mexico to build a new life. The Mexican and French conflict, with all its brutality, is presented as a kind of follow-up to the implosion just ending in the United States.

Shelby’s service to the Confederacy as a soldier and commander is framed by reports of atrocities as well as of his brilliance as a tactician. In Mexico, his hunger for war led him to propose—in a meeting with Maximilian—that he and his men take over the Mexican army and, after being reinforced by forty thousand Confederate soldiers, the government itself. Given this audacity, a hallmark of his style, Shelby’s actions and confession back in America at the end of his life are astounding. I’ll leave that part of this true story for readers to discover. It involves repentance—and Shelby’s great march from young unrepentant Rebel to older repentant American is a grand story for all ages and times.