Robert Pierce Forbes goes behind the scenes of the crucial Missouri Compromise, the most important sectional crisis before the Civil War, to reveal the high-level deal-making, diplomacy, and deception that defused the crisis, including the central, unexpected role of President James Monroe. Although Missouri was allowed to join the union with slavery, Forbes observes, the compromise in fact closed off nearly all remaining federal territory to slavery. Forbes's analysis reveals a surprising national consensus against slavery a generation before the Civil War, which was fractured by the controve