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

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

Going one step further, the court ruled that the Missouri Compromise — an 1820 legislative agreement that sought to limit the expansion of slavery in newly-added states or territories — was unconstitutional.

From Salon • May 15, 2022

In a 7–2 decision, the court declared that the relevant parts of the Missouri Compromise were unconstitutional, and that Scott remained enslaved as a result.

From Textbooks • Jul. 28, 2021

The exception occurred in 1819, prompted by the debate then raging over passage of the Missouri Compromise.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis