The Missouri Compromise of 1820 had several provisions: 1) Missouri was admitted to the Union as a slave state 2) Maine was admitted as a free state, and 3) in the future there would be neither slavery nor involuntary servitude permitted in the Louisiana territory north of the southern border of Missouri. Another allowed that the new territories of Utah and New Mexico be allowed to decide the issue of slavery for themselves, an idea known as "popular sovreignty" Some people believe that the FSA was designed to be inflammatory.
After the Compromise of 1850, and the acrimony that resulted from the FSA, most Southern lawmakers were skeptical at best about the intentions of their Northern counterparts.
Ultimately the passage of KN destryed the Whig party, divided the Democratic party, and created the Republican party