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The Missouri Compromise

The Missouri Compromise


Slavery in Missouri. When Missouri applied for admission to the Union as a state in 1819, slavery was already a way of life there. Even before the United States acquired the Louisiana Territory (including the parts that became Missouri), Spanish and French settlers had owned slaves. As part of the agreement to purchase the territory in 1803, the Jefferson administration promised to safeguard the settlers human property. By the time the population of Missouri (the name given to the territory encompassing the entire Louisiana Purchase besides the state of Louisiana, admitted to the Union in 1812) reached the sixty thousand people required to apply for citizenship, about ten thousand of those people were slaves. The application for statehood was far from routine: it precipitated an ominous sectional crisis that threatened the unity of the nation.

A Deadlock in Congress. When Congress received the application, James Tallmadge of New York added two amendments: one prohibiting the further introduction of slavery and another providing for the emancipation of all slaves in Missouri, who comprised 16 percent of the population, on their twenty-fifth birthday. In other words, Missouri would be admitted to the Union only if its residents agreed to create a state where slavery would eventually be prohibited. Tallmadges move had more to do with longstanding Northern resentment about the Souths added representation in Congressunder the Constitutions three-fifths rule, 60 percent of the Souths slaves were counted in determining a states representation in the House and the electoral collegethan humanitarian objections to slavery or equal rights for blacks. Tallmadges amendment passed the House, with the vote closely adhering to sectional lines, but the Senate defeated the measure. Unable to resolve the deadlock, Congress adjourned without passing the Missouri Enabling Act.

An Uneasy Compromise. The Missouri issue came up again early in the next Congress. As the votes the previous session had proven, the North controlled a bare majority in the House while the South, helped by the recent admissions of Alabama and Southern-oriented Illinois, controlled the Senate. A bitter debate raged for months in both chambers. Again, the argument turned on political influence rather than the rights of slaves or the morality of the institution. In 1820 Congress overcame its deadlock and hatched a compromise. This agreement, termed the Missouri Compromise, enabled Missouri to enter the Union as a slave state while the northernmost counties of Massachusetts became the free state of Maine. The scheme neutralized fears that the South would gain more influence in the Senate. Next, the South agreed to outlaw slavery north of 36°30 latitude, a line extending west from Missouris southern border. The compromise opened up the new territory of Arkansas (present-day Oklahoma and Arkansas) to slavery while barring the institution from the remainder of the Louisiana Purchase. As a result, Kansas, Nebraska, Colorado, Wisconsin, Minnesota, Iowa, Montana, Wyoming, and North and South Dakota all eventually joined the Union as free states. The plan satisfied Southern members of Congress, who viewed Arkansas as ideally suited for plantation slavery and the plains north and west of Missouri as little more than a treeless desert.

A Fire-Bell in the Night. The Missouri Compromise made it plain that sectional issues were a political tinderbox. It brought the Souths commitment to slavery and the Norths resentment of Southern political power into direct confrontation, revealing what was becoming an unbridgeable gulf between slave and free states. Thomas Jefferson, in retirement at Monticello, was distraught by the Missouri Compromise: a geographical line, coinciding with a marked principle, moral and political, once conceived and held up to the angry passions of men, will never be obliterated, Jefferson wrote. The dispute over Missouri, like a fire-bell in the night, awakened and filled me with terror. I considered it at once the knell of the Union. A seemingly simple matteradmitting two new states to the Unionhad bitterly divided a democratic government and staked out the West as the battleground over the rights and wrongs of slavery.


Glover Moore, The Missouri Controversy (Lexington: University of Kentucky Press, 1953);

Charles Sellers, The Market Revolution: Jacksonian America, 18151846 (New York: Oxford University Press, 1991).

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