In the Civil War, rough-and-tumble St. Louis played a key role as a strategic staging ground for the Union army. A citadel of free labor in a slave state, it also harbored deeply divided loyalties that mirrored those of its troubled nation. Until now, however, the fascinating story of wartime St. Louis has remained largely unchronicled.

By the mid-nineteenth century, St. Louis had become the nation's greatest inland city, providing a "gateway to the West," a riverine crossroads for national commerce, and an ideal base for expansion-minded industrialists from the abolitionist Northeast....

From the late colonial period through the Civil War, slavery developed as the most powerful obstacle to the triumph of liberal values in America. In the second quarter of the nineteenth century, the ambiguities of the revolutionary generation's accomodation of slavery gave way to a direct and violent conflict between northern liberalism and southern slavery. The character of the antislavery movement -- its relationship to broader discussions of morality, law, political economy, and mass politics -- and the expectations it raised for the postemancipation South are central themes of this...