1799
 
Dred Scott is born in Virginia as a slave of the Peter Blow family. He spent his life as a slave, and never learned to read or write.

1803
 
United States purchases Louisiana from France, extending federal sovereignty to an ill-defined territory west of the Mississippi.

1804
 
United States takes formal possession of what is now Missouri.

1820
 
After fierce debate, Congress admits Missouri as a slave state. The question of Missouri statehood sparks widespread disagreement over the expansion of slavery. The resolution, eventually known as the Missouri Compromise, permits Missouri to enter as a slave state along with the free state of Maine, preserving a balance in the number of free and slave states. The Compromise also dictates that no territories above 36o 30' latitude can enter the union as slave states. Missouri itself is l ocated at the nexus of freedom and slavery. The neighboring state of Illinois had entered the union as a free state in 1819, while in subsequent years Congress admits Arkansas as a slave state and Iowa as a free state.

1830
 
The Blow family moves to St. Louis, part of the wholesale migration of people from the southern states of the eastern seaboard to the newer slave states of the Mississippi Valley. The Blows sell Scott to Dr. John Emerson, a military surgeo n stationed at Jefferson Barracks just south of St. Louis. Over the next twelve years Scott accompanies Emerson to posts in Illinois and the Wisconsin Territory, where Congress prohibited slavery under the rules of the Missouri Compromise. During this ti me, Scott marries Harriet Robinson, also a slave. The Scotts later have two children. The Scotts are not alone in this movement. Slaves are constantly on the move, either forced to accompany their masters or sold as part of the ever-widening domestic s lave trade. Slave states and free states, which had previously respected one another's laws on slavery, become increasingly hesitant to enforce those laws as the argument over the expansion of slavery becomes increasingly heated. Slaveholders express pa rticular opposition to legal precedents that permit slaves to demand their own freedom after being transported to places (whether other states or foreign countries) that prohibit slavery.

1842
 
The Scott family returns to St. Louis with Dr. Emerson and his wife Irene.

1843
 
John Emerson dies. Mrs. Emerson hires out Dred, Harriet, and their children to work for other families in St. Louis.

1846
 
Dred and Harriet Scott sue Mrs. Emerson for their freedom in the St. Louis Circuit Court.

1847
 
The Circuit Court rules in favor of Mrs. Emerson, dismissing the Scotts' case but allowing the Scotts to refile their suit.

1850
 
The jury in a second trial decides that the Scotts deserve to be free, based on their years of residence in the non-slave territories of Wisconsin and Illinois.

1852
 
Mrs. Emerson, not wanting to lose such valuable property, appeals the decision to the Missouri Supreme Court. Lawyers on both sides agree that from now on appeals will be based on Dred's case alone, with findings applied equally to Harriet. The state Supreme Court overrules the Circuit Court decision and returns Scott to slavery.

1853-54
 
Scott, supported by lawyers who opposed slavery, files suit in the U.S. Federal Court in St. Louis. The defendant in this case is Mrs. Emerson's brother, John Sanford, who has assumed responsibility for John Emerson's estate. As a New Yor k resident and technically beyond the jurisdiction of the state court, Scott's lawyers can only file a suit against Sanford in the federal judicial system. Again the court rules against Scott.

1856-1857
 
Scott and his lawyers appeal the case to the U.S. Supreme Court. In Scott v. Sanford the Court states that Scott should remain a slave, that as a slave he is not a citizen of the U.S. and thus not eligible to bring suit in a federal court, and that as a slave he is personal property and thus has never been free.

The court further declares unconstitutional the provision in the Missouri Compromise that permitted Congress to prohibit slavery in the territories. In fact, the compromise is already under assault as a coalition of political leaders—some slaveholders, o thers westerners who resent the federal government's ability to dictate the terms of statehood—claim that territorial residents should be able to determine on what terms they enter the union. The decision in Scott v. Sanford greatly alarms the antislaver y movement and intensifies the growing division of opinion within the United State. The newly-formed Republican Party, which opposes the expansion of slavery, vigorously criticizes the decision and the court.

1857
 
Mrs. Emerson remarries. Since her new husband opposes slavery, she returns Dred Scott and his family to the Blow family. The Blows give the Scotts their freedom.

1858
 
Dred Scott dies of tuberculosis and is buried in St. Louis. He was buried in Wesleyan Cemetery at what is now the intersection of Grand and Laclede Avenues in St. Louis (now part of the campus of St. Louis University). In 1867, Wesleyan cemetary closed and the bodies were dis-interred and re-buried at other sites. Dred Scott's body was moved to an unmarked grave in Section 1, Lot No. 177, Calvary Cemetery, in north St. Louis County. In 1957 a marker was placed on Dred Scott's grave which reads:
"DRED SCOTT BORN ABOUT 1799 DIED SEPT. 17, 1858
DRED SCOTT SUBJECT OF THE DECISION OF THE SUPREME COURT OF THE UNITED STATES IN 1857 WHICH DENIED CITIZENSHIP TO THE NEGRO, VOIDED THE MISSOURI COMPROMISE ACT, BECAME ONE OF THE EVENTS THAT RESULTED IN THE CIVIL WAR"

1860
 
Abraham Lincoln is elected president in a political contest dominated by the discussion of slavery. South Carolina secedes from the Union, and the Civil War begins.