Clay County was settled primarily from migrants from the Upper
Southern states of Kentucky, Tennessee, and Virginia. They
brought slaves and slaveholding traditions with them, and quickly
started cultivating crops similar to those in Middle Tennessee and
Kentucky: hemp and tobacco. Clay was one of several counties settled mostly by
Southerners to the north and south of the Missouri River. Given their
culture and traditions, this area became known as Little Dixie. In 1860,
slaves made up 25% or more of the county's population. Residents generally
supported the Confederacy during the Civil War, as the Confederate
flag flew over the county courthouse for many years following the end of
the Civil War.
Many
members of the Latter Day Saint movement found refuge in Clay County
in November 1833. In 1836, mobs drove the members of the church from the county. Leaders
of this church, most notably Joseph Smith, were imprisoned for some months
in Clay County in the jail at Liberty. In May 2012, the LDS Church opened
a Kansas City Missouri Temple six miles southwest of the Liberty Jail
site at 7001 Searcy Creek Parkway in Kansas City, Missouri.