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Definition: Missouri Compromise from Philip's Encyclopedia

(1820-21) Effort to end the dispute between slave and free states in the USA. Largely the work of Henry Clay, it permitted Missouri to join the union as a slave state at the same time as Maine joined as a free state, preserving an equal balance between slave and free.

Summary Article: MISSOURI COMPROMISE OF 1820
From Encyclopedia of U.S. Political History

Under the terms of the Missouri Compromise, Missouri gained entry into the Union as a slave state, Maine came in as a free state, and slavery was "forever prohibited" from the vast unorganized lands remaining within the Louisiana Purchase north of the 36°30' parallel. The debates surrounding the Missouri Compromise represented the first time that the issues of slavery and race were fully and publicly aired in the new nation. Professing antislavery convictions firmly rooted in earlier disagreements over the South's increasingly "peculiar institution," Northern congressman, irrespective of party and with widespread popular support, challenged the South on a slavery-related issue. Coming as it did at the end of the so-called Era of Good Feelings, the resulting political crisis laid bare the growing and dangerous gap between the North and the South regarding the future of freedom and slavery in America, the fragile basis upon which the Union rested, and the troubling tension between the national commitment to human equality and the ugly reality of slavery and racial prejudice. Finally, by politicizing the slavery issue as never before, and tying it to the destiny of republican government in America, it prefigured the sectional controversy that led to civil war four decades later.

Background to the Controversy

The controversy began on December 18, 1818, when the Speaker of the U.S. House of Representatives, Henry Clay, presented a memorial from the territory of Missouri requesting statehood. Two months later, on February 13, 1819, in the midst of a discussion on Missouri's petition, New York representative James Tallmadge Jr. introduced an amendment to the bill that would have banned the further introduction of slavery into the prospective state and freed all children born of slaves already there on their 25th birthday. In effect, Tallmadge proposed to gradually abolish slavery in Missouri as a condition of statehood. His amendment immediately provoked a fierce and bitter debate that would consume Congress and much of the nation for the next two years.

Two days after Tallmadge placed his amendment before the House, a fellow New York Republican, John Taylor, spoke directly to his Southern colleagues, many of whom had professed their hatred of slavery in the past. Taylor expressed concern that a "slaveholding spirit" seemed to be advancing throughout the Union, and he urged them to embrace the opportunity Missouri presented to put their claimed antislavery principles into practice. No Northern restrictionist—as those who were in favor of checking the further growth of slavery were called—proposed to interfere with slavery in the existing slave states or to free slaves already in Missouri. Instead, Taylor and the Northern restrictionists sought only to block slavery's further expansion before it became so firmly implanted that it could never be uprooted. As everyone understood, the precedent set by the Missouri decision would likely apply to all the national territory beyond the Mississippi. Tallmadge himself best summarized the importance of the issue facing Congress. "Now is the time," he insisted. "It must be met … the extension of the evil must be prevented, or the occasion is irrevocably lost."

The Northern Restrictionist Attack on Slavery

During the Missouri crisis, Northerners denounced slavery as a moral and political evil that robbed its victims of their natural rights and individual liberty and denied the truth of the common origins of all humanity. The principles of the American Revolution, embodied in the Declaration of Independence and the Constitution, were championed as testaments to freedom and equality, as well as forthright repudiations of slavery. Northerners allowed that the Constitution permitted the continued existence of slavery, owing to the urgent need for national unity at the time of its adoption, but it was with the understanding that it applied only to the original slave states and the territory they had ceded to the new nation. They also took it for granted that, when deemed safe to do so, the South would enact a program of gradual emancipation and allow the federal government to restrict slavery's expansion into the West.

Northerners also attacked slavery for its wider social and economic impact on the nation. They compared the healthy, industrious free laborers of the North, with their well-cultivated farms, comfortable homes, superior roads and bridges, and thriving young manufacturers, with the poor whites, degraded blacks, exhausted old fields, bad roads, and general squalor believed to be common throughout the South. Slavery, they insisted, accounted for these differences. It rendered labor disgraceful and promoted idleness, poverty, and vice. If allowed to expand, slavery would effectively lock the North's hardworking laborers out of the territories, for they would be unwilling to place themselves in competition with slaves.

For Northerners, then, slavery not only extinguished human rights, it also weakened the nation's moral and material character, placed the freedom and mobility of white laborers at risk, and threatened the future happiness and prosperity of the entire country. This focus on slavery's baleful effects on national development furnished an added dimension to the antislavery persuasion, enhanced its popular appeal, and provided a powerful complement to the arguments based on America's Revolutionary ideals. During the course of the debates, Northern politicians favoring restriction were often accused of attempting to manipulate events to their personal political advantage, and no doubt some hoped to do so. Nevertheless, the political dimensions of the Missouri crisis can only be understood within the broader context of this antislavery appeal. A genuine hatred of slavery motivated most Northerners, as did a desire to avoid the ruinous impact of its spread on the future of the nation's republican institutions and on the character and aspirations of its people.

The question of race and the place of blacks in American society also entered into the attack on slavery. Despite pervasive racial prejudice throughout the North, many restrictionists displayed a surprising degree of tolerance and respect for some, if not all, black civil rights. In general, Northerners accepted black slaves' claims to freedom even if they rejected black claims to equality. The Missouri controversy, however, clearly exposed the tension between the widely held belief that all citizens of a republican government were entitled to equal rights and the contrary reality of intolerance and bigotry that increasingly marginalized free blacks and slaves in both the North and the South.

The South's Response

The South responded to the North's challenge forcefully and with spirit. Long discourses on the sanctity of states' rights, the limited power of the national government over local institutions, and the constitutional compromises related to slavery joined with hot-tempered threats to break up the Union and accusations that self-seeking men were bent on reducing the slave states to political impotence. Southerners also dismissed assertions that the Declaration of Independence and the Constitution applied to the nation's blacks, pointedly reminded Northerners of discriminatory laws and practices prevailing in their own states, and flatly declared that the Constitution sanctioned slavery. To be sure, many of them continued to express antislavery views, and some even prayed that the institution would someday wither and die. But nearly all Southerners maintained that any immediate steps toward emancipation were utterly impractical and dangerous, insisting that even a gradual plan to free America's slaves remained a hopeless dream. As such, unless America's leaders could come up with a prudent and safe program of liberation, slavery must endure and slave owners must share fully in the lands owned in common by the nation. More ominously, a number of Southern spokesmen forthrightly defended slavery, "without qualification or reserve," as an institution for which black Americans were best suited, and one that the federal government was obligated to support and uphold.

Southerners also spent much time vindicating their claim that the expansion of slavery was a humane, just, and sound policy. They insisted that dispersing the enslaved blacks throughout the West would reduce their numbers in proportion to the white population and lead to improved living conditions and greater protection from the occasional harshness of the system. Confine slaves to the old states of the Southeast, however, and their situation would worsen. Many proponents of this theory of "diffusion" also asserted that by thinning the concentration of slaves, a safer environment for all would result. Indeed, one of the most persistent themes to emerge in the Missouri debates revolved around the profound fear of slave insurrection. Southerners repeatedly turned to diffusion as an effective means to minimize this concern.

Ultimately, Southerners were nearly unanimous in their resolve that slavery must be allowed to expand into Missouri. Moreover, the South's rejection of a practical plan of gradual emancipation established that that the slave-owning states had no intention of putting their antislavery principles into practice. It also indicated that even seemingly moderate antislavery proposals would be met with angry defiance, and that slavery would be a lasting, and likely a permanent feature of American life. In short, by 1820, most Southerners had concluded that slavery was an evil for which no cure existed.

Compromise and Resolution

With the North and South so deeply divided over slavery and its expansion, passage of the Missouri Compromise proved to be a nearly insurmountable task. President James Monroe played a key behind-the-scenes role in preventing matters from spinning dangerously out of control. His handpicked floor leader and fellow Virginian in the Senate, James Barbour, also worked hard to bring about a peaceful settlement. In the House, Henry Clay combined charm with threats to win key votes from wavering Northern members. Clay's efforts gained him the nickname "the Great Compromiser." Senator Rufus King of New York and his House colleague John W. Taylor led the Northern effort to check slavery's growth. In the end, only the last-minute votes of a few Northern members of Congress, concerned that disunion would be the price of failure, secured enactment of the compromise.

The Missouri Compromise remains one of the most far-reaching and important pieces of legislation ever passed by Congress. The crisis raised slavery to a central place in American politics and revealed as never before the danger it posed to national unity and peace. As such, politicians would make great efforts to suppress the issue in subsequent years, but with limited success. By the 1840s, slavery once again took center stage—first over Texas annexation, and then over the question of its spread into the Western lands obtained from Mexico by war. The continuing significance of the compromise lay with the one remaining part of it still relevant—the 36°30' line of division. The North would come to enshrine this compromise measure as a sacred and inviolable compact, the South as a degrading and unconstitutional restriction on the right of slave owners to carry their bondsman into the national domain. The 1854 Kansas-Nebraska Act repealed the compromise; the Dred Scott decision, handed down by the United States Supreme Court in 1857, declared it to be unconstitutional. An outraged Northern majority interpreted these acts to be positive proof that slave owners were in control of the federal government and represented a threat to their liberty, thus laying the basis for the formation of the Republican Party, which was dedicated to blocking slavery's further expansion. The election of Abraham Lincoln in the 1860 presidential contest finally brought about Southern secession from the Union and the long-delayed and terrible Civil War between the free and slave states.

The vast unorganized Western territory north of the 36°30' parallel was closed to slavery with the passage of the Missouri Compromise in 1820, while the Arkansas Territory became open to slavery. There were now 16 official slave states or territories and 14 official free states or territories in the United States.

Bibliography and Further Reading
  • Annals of Congress: Sessions of the 15th and 16th Congress, 1817-1821. Washington, D.C.: Gales & Seaton, 1834-1856. Available online from the Library of Congress,
  • Brown, Richard H. "The Missouri Crisis, Slavery, and the Politics of Jacksonism." South Atlantic Quarterly 65 (winter 1966): 55-72.
  • Cunningham, Noble E. Jr. The Presidency of James Monroe. Lawrence: University Press of Kansas, 1996.
  • Fehrenbacher, Don E. The Slaveholding Republic: An Account of the United States Government's Relation to Slavery. New York: Oxford University Press, 2001.
  • Fehrenbacher, Don E.. The South and Three Sectional Crises: Friends, Foes, and Reforms. Baton Rouge: Louisiana State University Press, 1980.
  • Forbes, Robert Pierce. The Missouri Compromise and Its Aftermath: Slavery and the Meaning of America. Chapel Hill: University of North Carolina Press, 2007.
  • Hammond, John Craig. Slavery, Freedom, and Expansion in the Early American West. Charlottesville: University of Virginia Press, 2007.
  • Matthew, Mason. Slavery and Politics in the Early American Republic. Chapel Hill: University of North Carolina Press, 2006.
  • Glover, Moore. The Missouri Controversy: 1819-1821. 1937. Reprint, Gloucester, MA: Peter Smith, 1967.
  • Richards, Leonard L. The Slave Power: The Free North and Southern Domination, 1780-1860. Baton Rouge: Louisiana State University Press, 2000.
Michael J. McManus
© 2010 CQ Press, A Division of SAGE

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