Redemption Falls by Joseph O'connor (Star of the Sea #2)

From the author of international bestseller Star of the Sea comes this tale of hatreds and mercies, of balladry and the blues, war and peace. It is an epic novel and an unforgettable love story.
1865: The American Civil War is ending. Eliza Duane Mulvey sets out from Lafayette, Louisiana, the town her mother Mary Duane called home. Alone, she walks across a devastated country in search of a youngster she has not seen in four years. One of the hundred thousand children drawn into the war, his fate has been mysterious and will prove extraordinary.
It’s a walk that will have consequences for many seemingly unconnected survivors: a love-struck cartographer, a beautiful Latina poetess, rebel guerrilla Johnny Thunders, runaway slave Grace McNeile, the mercurial revolutionary Giacomo O’Keefe, who commanded a brigade of Irish immigrants in the Union Army and is now Governor of a western wilderness where nothing is as it seems.