In the early 1800s abolition and back-to-Africa movements spread through the cities of the North, encouraged by antislavery books, articles, speeches, and sermons. Nevertheless, a large proportion of white Americans, even Northern white Americans, still viewed slavery as an unfortunate evil that could never be properly solved. To recolonize the slaves to Africa was impractical; to abolish slavery entirely would bring a flood of jobless blacks into the cities, causing social and economic chaos. During the 1830s William Lloyd Garrison, a Northern journalist, founded the Liberator to fight for an end to slavery, but he found himself nearly lynched in the liberal city of Boston—the revolutionary "Cradle of Liberty"—for his stand.

The abolition movement also brought a strong counterreaction in the South where—as Southern planters were always quick to point out—cotton was providing the nation with its most...