Why did so many thousands of settlers pull up stakes and undertake the arduous journey to the frontier in 18th and 19th-century America?" While the desire for a more prosperous future figured prominently in their decisions, so did another, largely overlooked factor -- the presence of slavery and the growing number of blacks, both free and slave, in the eastern half of the United States. Poor white farmers, particularly those in the Upper South, found themselves displaced by the spreading of the plantation system. In order to survive economically they were chronically forced to move further inland. As they did so, they brought with them a deep animosity toward the enslaved blacks whom they blamed for this uprooting. Wherever these "plain folk" farmers subsequently settled -- in Kentucky, the free states north of the Ohio River, Missouri, and the outpost of Oregon, they sought to erect legal barriers to prevent slavery from taking hold as well as to deter the migration of free blacks who would otherwise compete for jobs and endanger white society. The pushing back of the frontier can be seen as an attempt to escape the complexities of a biracial nation and preserve white homogeneity by creating sanctuaries in these Western lands. The political struggle to establish more free states west of the Mississippi also reflects this goal: white nominally opposed to slavery, many "free staters" were most concerned about keeping all blacks at bay. "Race to the Frontier" is the first book to trace the impact of this racial hostility throughout the settlement of the West, from the days of colonial Virginia up to the Civil War. It clearly demonstrates how closely racial prejudice, economic growth, and geographical expansion have been entwined in American history.