Dred Scott was a black slave who was born in Southampton County, Virginia in 1795, and who made legal and constitutional history in 1848 by suing for his freedom. His case was based on the grounds that he had lived intermittently for years in a free territory with his former owner, who was an army surgeon. Originally his master took him from Missouri (a slave state) to Illinois (a free state). Because he had lived in a free territory, he therefore then should continue to be a free man. In Missouri, after a second trial, the Missouri District Court ruled in Scott's favor, however the Missouri Supreme Court reversed this decision.
A legal battle ensued that involved a number of petitions and appeals, until it was brought before the United States Supreme Court. Taking eleven years to be heard, in May 1857, Supreme Court Justice Roger B. Taney ruled in a majority opinion that challenged the Missouri Compromise, pushing the country closer to war.
At this time in 1857, Southerners were demanding protection of their property rights concerning slaves, and Northerners were fearful that a decision against Scott would void the Missouri Compromise, in turn opening up the Western lands to slavery.
The Missouri Compromise of 1820 came about when the Missouri territorial assembly petitioned Congress for admission to the Union in 1818. At this time, the United States consisted of twenty-two states, eleven of which were free and eleven that were slave. In deciding whether to admit states, Congress attempted to alternate between slave and free states, in order to maintain a balance between them. However, in Missouri at this time, there were about three thousand slaves living there. To admit Missouri as a slave state would have upset the balance between free and slave states, giving the South in the Senate an advantage, but not in the House where by virtue of population alone, the Northerners had 105 votes to the Southerners' 81.
To attempt to limit slavery in Missouri and in the West, New York Representative James Tallmadge proposed on February 13, 1819 an amendment to prohibit slavery from the territory. This measure passed in the House but was blocked in the Senate by Southern legislators. With no resolution, the measure was debated back and forth when in the fall of 1819, Maine separated from Massachusetts and thus petitioned for admission to the Union. This broke the stalemate and Congress used this opportunity by passing acts that enabled Maine and Missouri to draft constitutions and form their own state governments.
The constitution that Maine developed was passed by Congress uncontested. However, there were increasing anti slavery feelings in the United States that forced Congress to address the expansion of slavery into the Louisiana Purchase where slave holders had begun to settle. In their quest to avoid an imbalance between slave and free states in the Louisiana Purchase territory, Illinois Senator Jesse B. Thomas introduced a proposal to admit Missouri as a slave state but further restricting slavery thereafter in the Louisiana Purchase to land below the latitude 36 30'. The Senate agreed, passing the Missouri Compromise, as well as did the House following a short debate. Consequently, Missouri was admitted to the Union the following year on March 2, 1821.
In 1850-1851, when the slavery issue threatened to split the nation again, the Congress honored the 36 30' boundary lines in the Compromise of 1850. However, four years later, the Kansas-Nebraska Act voided the Missouri Compromise, which in turn forced the nation closer to war.
In the case of Dred Scott, the Supreme Court decision confirmed expectations in the North. The court ruled that Scott had no right to sue in Federal Court because blacks did not possess citizenship, and ignored his residence in the North as grounds for his freedom. The court further denounced the anti slavery provision of the Missouri Compromise as unconstitutional because it contradicted the Fifth Amendment of the Constitution that guaranteed protection of private property.
However, Dred Scott and his family were freed in May 1857 when their ownership was transferred, and as a free man, he became a hotel porter in St. Louis, Missouri. Dred Scott died there in c.1858.
One of the results of the decision of the Supreme Court by ruling against Scott was that it did heighten anti slavery support for Abraham Lincoln and the Republican Party.