In an effort to preserve the balance of power in Congress
between slave and free states, the Missouri
Compromise was passed in 1820 admitting Missouri as a
slave state and Maine as a free state. Furthermore, with
the exception of Missouri, this law prohibited slavery in
the Louisiana Territory north of the 36° 30´ latitude
line. In 1854, the Missouri Compromise was repealed by the
Kansas-Nebraska Act. Three years later the Missouri Compromise
was declared unconstitutional by the Supreme Court in the
Dred Scott decision, which ruled that Congress did not have
the authority to prohibit slavery in the territories.
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Century of Lawmaking for a New Nation
This collection contains congressional publications from 1774 to 1875, including debates, bills, laws, and journals.
- February 8 through February 17, 1820- The
Senate debated the admission of Maine and Missouri.
- February 16, 1820 - The Senate
agreed to unite
the Maine and Missouri bills into
- February 17, 1820 - The Senate agreed to an
amendment that prohibited
slavery in the Louisiana Territory north of the
36° 30´ latitude line, except for Missouri,
and then agreed to the final version of the bill by
a vote of 24 to 20.
- March 1, 1820 - The House
of Representatives passed its own bill, which
admitted Missouri without slavery, by a vote of 91 to 82.
- March 2, 1820 - A House-Senate conference agreed to the Senate's version of the bill.
- March 2, 1820 - The House
voted 90 to 87 to allow slavery in Missouri.
- March 2, 1820 - The House
to 42 to prohibit slavery in the Louisiana Territory north
of the 36° 30´ latitude line.
- March 6, 1820 - President James Monroe signed the Missouri Compromise.
State Papers contain the legislative and executive documents of Congress during the period 1789 to 1838. References in the American State Papers to the Missouri Compromise include:
- Application of Missouri for admission into the union as a state, December 29, 1819.
- Prohibition of slavery in Missouri, January 12, 1820.
- Prohibition of slavery in Missouri, January 18, 1820.
- Approval of the constitution, and admission of Missouri into the union, November 23, 1820.
- Admission of Missouri into the Union, February 10, 1821.
The James Madison Papers
The James Madison Papers from the Manuscript Division at the Library of Congress consist of approximately 12,000 items captured in some 72,000 digital images.
References to the Missouri Compromise include:
- James Madison to Robert Walsh, November 27, 1819. Missouri Controversy, "On the whole, the Missouri question, as a constitutional one, amounts to the question whether the condition proposed to be annexed to the admission of Missouri would or would not be void in itself, or become void the moment the territory should enter as a State within the pale of the Constitution. And as a question of expediency & humanity, it depends essentially on the probable influence of such restrictions on the quantity & duration of slavery, and on the general condition of slaves in the U. S." [Transcription]
- James Madison to James Monroe, February 10, 1820, "It appears to me as it does to you, that a coupling of Missouri with Maine, in order to force the entrance of the former thro' the door voluntarily opened to the latter is, to say the least, a very doubtful policy..." [Transcription]
- James Madison to James Monroe, February 23, 1820, "The pinch of the difficulty in the case stated seems to be in the words "forever," coupled with the interdict relating to the Territory N. of L 36° 30'. If the necessary import of these words be that they are to operate as a condition on future States admitted into the Union, and as a restriction on them after admission, they seem to encounter indirectly the argts. which prevailed in the Senate for an unconditional admission of Missouri." [Transcription]
Search Madison's Papers to find additional letters discussing the Missouri Compromise.
The James Monroe Papers
The James Monroe Papers at the Manuscript Division of the Library of Congress consist of approximately 5,200 items dating from 1758 to 1839. Monroe (1758–1831) was the fifth president of the United States, and one of 23 presidents whose papers are at the Library of Congress.
- President James Monroe's notes, February 13, 1820, on the Missouri Compromise, "The idea was that if the whole arrangement, to this effect, could be secured, that it would be better to adopt it, than break the union. Neither did Mr. Barbour, nor any other person alluded to, favor this, but to save the union, believing it to be in imminent danger."
- Thomas Jefferson to James Monroe, March 3, 1820, "I am indebted to you for your two letters of Feb. 7. & 19. this Missouri question by a geograpical line of division is the most portentous one I have ever contemplated. King is ready to risk the union for any chance of restoring his party to power and wriggling himself to the head of it. nor is Clinton without his hopes nor scrupulous as to the means of fulfilling them. I hope I shall be spared the pain of witnessing it either by the good sense of the people, or by the more certain reliance; the hand of death. on this or that side of the Styx I am ever and devotedly yours." [Transcription]
Thomas Jefferson Papers at the Library of Congress
The complete Thomas Jefferson Papers from the Manuscript Division at the Library of Congress consists of approximately 27,000 documents.
- Thomas Jefferson to William Short, April 13, 1820, "...the Missouri question aroused
and filled me with alarm...I have been among the most
sanguine in believing that our Union would be of long
duration. I now doubt it much..." [Transcription]
- Thomas Jefferson to John Holmes, April 22, 1820, "I thank you, Dear Sir, for the copy you have been so kind as to send me of the letter to your constituents on the Missouri question. it is a perfect justification to them. I had for a long time ceased to read newspapers or pay any attention to public affairs, confident they were in good hands, and content to be a passenger in our bark to the shore from which I am not distant. but this mementous question, like a fire bell in the night, awakened and filled me with terror. I considered it at once as the knell of the Union. it is hushed indeed for the moment. but this is a reprieve only, not a final sentence." [Transcription]
Papers to find additional letters discussing the Missouri
Back in Time: Missouri Became the 24th State, August
This exhibition focuses on the legacy of Thomas Jefferson--founding
father, farmer, architect, inventor, slaveholder, book
collector, scholar, diplomat, and the third president
of the United States. A section on the
West contains another copy
of the letter in which Jefferson writes that the
Missouri question, "like a fire bell in the night,
awakened and filled me with terror. I considered it at
once as the knell of the Union."
Maine became the twenty-third state on March 15, 1820.
Missouri entered the Union as the twenty-fourth state
on August 10, 1821.
Documents, Missouri Compromise, National Archives
and Records Administration
Missouri Compromise, The Lehrman Institute
The Missouri Compromise, ushistory.org
Fehrenbacher, Don E. The South and
Three Sectional Crises.
Baton Rouge: Louisiana State University Press, 1980. [Catalog
Robert Pierce. The Missouri Compromise
and Its Aftermath: Slavery & the Meaning of America.
Chapel Hill : University of North Carolina Press, 2007. [Catalog
Moore, Glover. The Missouri Controversy,
Mass.: P. Smith, 1967. [Catalog
Shoemaker, Floyd Calvin. Missouri's
Struggle for Statehood, 1804-1821. New York: Russell & Russell, 1969. [Catalog
Burgan, Michael. The Missouri Compromise. Minneapolis: Compass Point Books, 2006. [Catalog
Gold, Susan Dudley. The Missouri Compromise. New York: Marshall Cavendish Benchmark, 2011. [Catalog
Hinton, KaaVonia. To Preserve the Union: Causes and Effects of the Missouri Compromise. North Mankato, Minn.: Capstone Press, 2014. [Catalog
Lanier, Wendy. What Was the Missouri Compromise?: And Other Questions About the Struggle Over Slavery. Minneapolis: Lerner Publications, 2012. [Catalog