Formed January 29, 1841 (78th county)
Saint Clair County (9,287), Osceola (927), Appleton City (1,032)
The yellow brick Art Deco courthouse was constructed in 1916. The facility is on the town square at 2nd, Pine, 3rd and Chestnut streets. Missouri State Highway 13 passes 13 blocks to the northeast of the location. The structure has been enlarged. There were 1842 and 1866 courthouses also in Osceola, the only county seat. Both of these structures burned. Clifton B. Sloan was the building architect for the current courthouse. Local pictures and a list of county veterans are inside the building. Saint Clair County was formed on January 29, 1841 from Native American Territory as the 78th county. The county is named for Northwest Territory Governor Arthur Saint Clair. The county seat is named for the Native American chief.
Saint Clair County government consists of a sheriff, an administrator, an attorney, a collector, a coroner, an assessor and a clerk (executive). It has 3 Commissioners (legislative.) One Circuit Court Judge serves Saint Clair, Bates, and Henry counties and One County Court Judge and a court clerk serve Saint Clair County (judicial.) The county is in the southwest part of the state. Kansas City, Missouri is northwest and Springfield, Missouri is south of the county. The county center is 11 miles Southwest of Osceola nearer Roscoe. The county is surrounded clockwise by Henry, Benton, Hickory, Polk, Cedar, Vernon, and Bates counties.
The area of the county is 677 square miles. It is 36 out of 115 in the state. It ranks 89 out of 115 in population in the state. It has a density of 13.7 persons per square mile making it 93 out of 115 in the state. St. Clair County has 30.6% of its population in its incorporated areas. United States Highway 54 clips the southeast part of the county east to west from Hickory County, east, to Cedar County, south. The county looks like a small letter r facing down. Osceola is in the eastern third of the county. Appleton City is in the northwest corner of the county. Osceola is the county seat and Appleton City is the largest city. Osceola is 10.0% of the county population while Appleton City is 11.1% of the county population. The county seat is pronounced OE-CEE-OE-LA.
Appleton City
Collins
Gerster
Lowry City
Osceola
Roscoe
Vista