Historical Timeline
 1817  The territory of Missouri applies for statehood.
 1820 The Missouri statehood controversy became a national issue as the issue of slavery was debated.  The "Missouri Compromise" allowed Missouri to enter the Union as a slave state and Maine to enter as a free state, thus keeping the balance of slave and free states equal in Congress.  Although Missouri was allowed to enter as a slave state, the remaining portion of the Louisiana Purchase area north of the 36  30' line was to be forever free of slavery.  
 1821 Missouri was admitted to the Union as a slave state.
 1857 The Dred Scott decision was handed down by U.S. Chief Justice Roger B. Taney; the case of originated in St. Louis.  Under Missouri statutes, in 1846 Scott was allowed to sue for his freedom from slavery based on the fact that he had previously lived in a free territory (Wisconsin) before his return to the slave state of Missouri.