Slavery and the road to civil war

History of the USA · Expansion and sectional conflict. The idea in plain words, the rules to remember, the mistake to avoid and a worked example, written and checked by Mega Lecture.

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The idea

For forty years Congress kept the Union together by compromise over one question: could slavery spread into the western territories? The Missouri Compromise (1820) drew a line at 36°30'. The Compromise of 1850 dealt with the land won from Mexico.

The balance broke in the 1850s. The Kansas-Nebraska Act (1854) let settlers decide (popular sovereignty) and so cancelled the 1820 line. Violence followed in Kansas, and the Republican Party was formed to stop the spread of slavery. In Dred Scott (1857) the Supreme Court said Congress could not ban slavery in the territories at all.

When Lincoln, a Republican, won in 1860 on Northern votes alone, the Southern states began to secede.

Rules to remember

Common mistake

In 1860 Lincoln and the Republicans promised to stop slavery spreading into the territories, not to abolish it where it already existed. Do not write that he was elected as an abolitionist.

Worked example

Which did more to destroy the Missouri Compromise line: the Compromise of 1850 or the Kansas-Nebraska Act?

  1. The Compromise of 1850 dealt with land taken from Mexico, which was outside the Louisiana Purchase.
  2. Kansas and Nebraska lay inside the Louisiana Purchase and north of 36°30', where slavery had been barred since 1820.
  3. The 1854 Act opened them to slavery if settlers voted for it, so it repealed the line directly.

Answer: The Kansas-Nebraska Act of 1854. The Supreme Court then declared the 1820 line unconstitutional in Dred Scott (1857).

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