Legislation · 1820

Missouri Compromise

To settle a bitter sectional dispute over Missouri’s bid for statehood, Congress paired the admission of Missouri as a slave state with that of Maine as a free state, preserving the balance between free and slave states in the Senate. The act of March 6, 1820, also prohibited slavery in the rest of the Louisiana Purchase north of latitude 36°30′, outside Missouri itself.

“That in all that territory ceded by France to the United States, under the name of Louisiana, which lies north of thirty-six degrees and thirty minutes north latitude, not included within the limits of the state, contemplated by this act, slavery and involuntary servitude … shall be, and is hereby, forever prohibited…”

March 6, 1820

Why it matters

The line held for more than three decades; its repeal by the Kansas-Nebraska Act in 1854 helped spark the founding of the Republican Party, and in Dred Scott v. Sandford (1857) the Supreme Court declared the restriction unconstitutional.

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Primary Source

The original record, reproduced or linked from the institution that holds it. Primary sources show what people said and did in their own words.

Subjects

slavery territories sectional conflict westward expansion

From the library

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