The author, daughter of Julia Ward Howe, traces the hymn's origins from decades of anti-slavery agitation through crises such as the Kansas conflict, describes her mother's visits to the Army of the Potomac and the spontaneous composition of the famed Civil War anthem, and follows its rapid adoption by troops. Chapters document notable occasions when the song was sung, the author's own recitations, contemporary tributes, other wartime poems by her mother, and the family legacy of commitment to freedom, situating the hymn within broader political and cultural currents of the era.