5.4 The Compromise of 1850

Crisis Over the Mexican Cession

The U.S. victory in the Mexican-American War (1848) added vast new western territory, reigniting debate over slavery's expansion. The Wilmot Proviso (1846) proposed banning slavery in any land gained from Mexico; it passed the House but failed in the Senate, deepening sectional tension between North and South over whether new states would be free or slave.

Terms of the Compromise

Crafted by Henry Clay and passed through Stephen Douglas's maneuvering, the Compromise of 1850 admitted California as a free state, let Utah and New Mexico decide slavery via popular sovereignty, ended the slave trade (not slavery) in Washington D.C., settled the Texas-New Mexico border, and strengthened the Fugitive Slave Act, requiring citizens to help capture escaped enslaved people.

Fragile Peace, Lasting Fallout

The compromise delayed war but satisfied no one fully. Northerners resented the harsh Fugitive Slave Act, spurring resistance and abolitionist works like Uncle Tom's Cabin. Southerners feared losing political balance as free states grew. The deal's fragility set the stage for further conflict, including the Kansas-Nebraska Act of 1854.

Key terms

Wilmot Proviso

1846 proposal to ban slavery in territory gained from Mexico; passed House, failed in Senate.

Compromise of 1850

Series of laws admitting California as free, using popular sovereignty in Utah/NM, ending D.C. slave trade, and strengthening the Fugitive Slave Act.

Popular sovereignty

Principle letting territorial residents vote on whether to allow slavery.

Fugitive Slave Act of 1850

Law requiring citizens and officials to help capture and return escaped enslaved people; sparked Northern resistance.

Stephen Douglas's role

Broke Henry Clay's omnibus bill into separate measures, securing passage of the Compromise of 1850.

Try an AP-style question

The Compromise of 1850 admitted California as…

1. a slave state
2. a territory with no rules
3. a free state
4. a Mexican province