Historical U.S. territorial maps showing the Missouri Compromise of 1820, the Compromise of 1850, and the Kansas-Nebraska Act of 1854 with color-coded regions and a provided key.

- The Missouri Compromise of 1820 established a line at 36°30' latitude, north of which slavery was prohibited in the Louisiana Purchase territory (except Missouri), and south of which it was permitted.
- The Compromise of 1850 admitted California as a free state, allowed popular sovereignty in Utah and New Mexico territories, abolished the slave trade in Washington D.C., strengthened the Fugitive Slave Act, and settled Texas’s boundary dispute by compensating it with federal assumption of its debt.
- The Kansas-Nebraska Act of 1854 repealed the Missouri Compromise by allowing popular sovereignty in Kansas and Nebraska territories, leading to violent conflict known as “Bleeding Kansas,” and intensified sectional tensions that contributed to the Civil War.