Chapter 18: A Secession Crisis Over Slavery Is Avoided with the Missouri Compromise

In 1819 the regional detente reached on slavery at the Constitutional Convention almost falls apart when the Missouri Territory seeks admission to the Union as a Slave State.

Northern politicians point out that its immediate adjacency to the Free State of Illinois should override the settlers’ wishes. But Southerners argue that Missouri is part of the Louisiana Purchase land acquired from France in 1803, and not covered by the earlier Ordinances.

This becomes the first test of the South’s economic need to expand slavery into the west, and they threaten Disunion if their demand is not met.

Resolution comes from Speaker of the House, Henry Clay, in his 1820 Missouri Compromise legislation. He looks at a map and extends the previous line of demarcation where the Ohio River runs into the Mississippi into the west at longitude 36’30”. New Louisiana land territories north of the line will become Free Sates and those to the south Slave States. With the one exception being Missouri, offered up to gain enough support to pass the bill.

The Compromise passes, and for the next 30 years it will dampen most Southern calls for secession.