Missouri Compromise

American  

noun

U.S. History.

1. an act of Congress (1820) by which Missouri was admitted as a Slave State, Maine as a Free State, and slavery was prohibited in the Louisiana Purchase north of latitude 36°30′N, except for Missouri.

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Missouri Compromise Cultural  

1. A settlement of a dispute between slave and free states, contained in several laws passed during 1820 and 1821. Northern legislators had tried to prohibit slavery in Missouri, which was then applying for statehood. The Missouri Compromise admitted Missouri as a slave state and Maine as a free state, and prohibited slavery in territory that later became Kansas and Nebraska. In 1857, in the Dred Scott decision, the Supreme Court declared the compromise unconstitutional.

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Example Sentences

But beginning around 1820, the year of the Missouri Compromise, slavery began to dominate American politics, suffusing even issues that one might think were unrelated, such as federal funding for infrastructure projects.

From Salon • Jul. 26, 2025

And so, first of all, we minimized the slavery controversy which convulsed the nation from the Missouri Compromise down to the Civil War.

From Salon • Apr. 16, 2025

Then came the 1857 Dred Scott decision, which struck down the Missouri Compromise and denied Congress the right to prohibit slavery in the nation’s territories.

From Salon • Mar. 3, 2024

By the 1850s, many in the South were also growing resentful of the Missouri Compromise of 1820, which established the 36° 30' parallel as the geographical boundary of slavery on the north-south axis.

From Textbooks • Dec. 30, 2014

In that same year, 1820, the year of the Missouri Compromise, Thomas Garrett and his wife, Sarah, both Quakers, moved from Darby, Pennsylvania, to Wilmington, Delaware.

From "Harriet Tubman: Conductor on the Underground Railroad" by Ann Petry