In 1803, The U.S. doubled in size practically overnight when it purchased about 828,000 square miles of territory from France. President Thomas Jefferson had sent some envoys (including future president James Monroe) to Napoleon to see about buying the Port of New Orleans as a way of protecting it from Spanish blockades. Instead, France surprised everyone by offering a huge territory that stretched from the Gulf of Mexico to Canada. Apparently, Napoleon, who'd hoped the territory would supply goods to support his lucrative sugar business in Haiti, had found it too much of a hassle and expense to maintain the sprawling Louisiana territory.
Napoleon made the U.S. an offer it couldn't refuse: $15 million bucks for the whole shebang. That's less than 3 cents per acre, a steal even in today's money. The envoys, who'd been authorized to offer $10 million just for New Orleans and its neighborhood, jumped on the deal and relayed the news to Jefferson.
As soon as the purchase was a done deal, trouble started a-brewin'. Everyone knew there would eventually be states made out of all that territory, which raised the eternal question: would they be slave or free? There had always been a delicate balance in the new nation of slave and free states; would this gigantic purchase upset the balance?
Over the next fifty years, the Purchase would cause major conflict between north and south. Thirteen new states were eventually created from it, and there were battles over slavery in almost every one. Much of the legislation that regulated slavery in the states came from arguments over the territory gained in the Louisiana Purchase, the gift that kept on giving (source).
Psst: we've got a whole learning guide on this one, too.
From the nation's founding, there'd been a policy of maintaining a delicate balance of slaveholding vs. free states so that sectional conflict might be avoided and no state would feel they'd have to bolt from the Union. If a free state was admitted to the Union, a slave state got an invitation. Otherwise, one region of the country would have an advantage in the Senate and might pass bills that disadvantaged the other. Like outlawing slavery, for instance.
When the Louisiana Purchase doubled the size of the U.S., people knew that this conflict could be ramped up big-time as new states would be formed and request admission to the Union.
By 1818, Missouri had gotten populous enough for apply for statehood. One of the states created out of the Louisiana Purchase, it asked for admission as a slave state. The problem was that there wasn't a free state to admit and keep the balance. When Alabama was admitted to the Union as a slave state in 1819, the fight over Missouri got worse. Admitting Missouri as a slave state would give the South a Senate majority.
An amendment allowing Missouri to keep its current slaves but not to have any others (and to emancipate everyone at age 25) was shot down.
Then, just as it did with its L.L. Bean Baxter State Parka which will keep you warm down to -45 degrees, Maine came to the rescue. Carved out of Massachusetts territory, it wanted admission as a Free State.
Problem solved? Not really. The balanced was maintained for now, but what about future states?
Enter Speaker of the House Henry Clay—the same guy who'd also save the day in 1850.
Clay proposed an imaginary boundary to be drawn east-west across the territory of the Louisiana Purchase at the 33 30' latitude line. North of the line, all future states would be free (Missouri got a pass); south of it, slavery was permitted. President Monroe signed the bill on March 5, 1820, and Clay earned the nickname "The Great Pacificator."
The Missouri Compromise did keep the peace; or, depending how you looked at it, kicked the can down the road for another Congress to deal with later.
P.S. For more on this compromise, head over to our learning guide on it.
Former Prez Jefferson thought the Compromise was a disaster for the Union, that it would guarantee secession at some point (source). After all, who was the federal government to dictate to states whether or not they could allow slavery? Unfortunately, he'd eventually be proven right, but not for another forty years.
Henry Clay and his Compromise of 1850 had calmed things down for the time being between North and South. But the sectional conflict never really went away, and it erupted again when the Nebraska Territory was organized. No problem, right? The Missouri Compromise said that it would be a be free state when it joined the Union—it was above the imaginary line drawn in 1820 separating free from slaveholding states.
The southern states went into a panic, as usual, that the balance of slave and free states would be upset and they'd be outnumbered in the Senate. The abolitionist movement was gaining steam up north and who knows what would happen with new free states upsetting the balance.
In the mid-19th century, Americans were all in for building a transcontinental railroad. Now that they owned a good part of the continent, it seemed like a decent possibility. Problem was, every city in the country wanted to have the railroad stop there and enjoy the economic boon it would provide. Stephen Douglas, a senator from Illinois, was especially hot to have the train stop in Chicago; he owned land there and knew its value would go through the roof if the railroad went through the city. Kind of like how rents in Boston can depend on how close you are to the T.
Senator Douglas had another wish: to be President Douglas. The Southern states, who also wanted the railroad to run through New Orleans, decided to cut a deal with him. They'd allow a northern route instead if Douglas would figure out a South-friendly way to deal with Nebraska. Like letting the territory decide for itself if it wanted to own slaves. "Popular sovereignty," was the name Douglas gave to this idea.
Douglas decided to recommend dividing the territory in two, creating Nebraska and Kansas territories. Each could decide it's own fate regarding slavery.
Seemed like a win-win to Douglas. After all, everyone doubted that Nebraska would ever permit slavery, and everyone figured that Kansas would. Balance maintained, railroad through Chicago, and President Douglas. Another Great Compromise like the Missouri and the Compromise of 1850.
Except it wasn't.
The Kansas-Nebraska Act was signed into law in 1854, effectively repealing the Missouri Compromise and its imaginary line between slave and free states.
Almost immediately, abolitionists flooded into Kansas to try and influence the writing of the state constitution to abolish slavery. Pro-slavery posses from Missouri showed up, too, burning and looting and threatening the Free-Staters. What ensued was an era called "Bleeding Kansas." By the time a state constitution was finally approved, more than 200 people had been killed (source).
And that constitution? It was abolitionist. Kansas was admitted to the Union as a Free State in 1861. Three months later, the nation was at war.
In 1833, Army surgeon John Emerson purchased a slave, Dred Scott, and when Emerson moved to the Wisconsin Territory, he took Scott with him. Because of the Missouri Compromise, Wisconsin was a free territory. Emerson and the Scott family moved again back to Louisiana then to St. Louis, where Emerson died and left his slaves to his wife.
Dred Scott sued for his freedom, claiming that living in Wisconsin, where slavery was prohibited, made him essentially a free man. A Missouri Court agreed, but Emerson's widow appealed to the Missouri Supreme Court, who overturned the lower court's verdict. Scott again tried to sue, but the court said that as a descendant of slaves, he was the private property of Emerson's widow and a court couldn't take away property.
Scott had one last shot at freedom—appealing to the Supreme Court of the United States.
At first, the Supremes refused to even hear the case, because, as he was legally determined to be a slave by Missouri, Scott wasn't a citizen and only citizens could bring cases before the Court. They finally relented, but decided against Scott and upheld the Missouri Supremes' decision.
For good measure, they threw in there that, PS, the Missouri Compromise was unconstitutional. The feds had no business dictating to the states about slavery or the lack of it. So even if Wisconsin was supposed to be a free state due to the Compromise, it was an illegitimate law. Dred Scott could not catch a break.
This was only the second time that the Supreme Court declared a federal law to be unconstitutional. Savvy Shmoopers know the first time. C'mon, we'll give you a sec.
Correct: Marbury v. Madison. Extra credit all around.
Anyway, the Dred Scott case demonstrated that promises…we mean compromises…are made to be broken. Like the Missouri Compromise, Compromise of 1850, and Kansas-Nebraska Act, it was another step along the road to the secession. Slavery was an issue that just refused to go away. Not being able to be settled in the legislature, it had to be settled on the bloody battlefields of the Civil War.