|MO State Facts|
|Territory: June 4, 1812|
|Statehood: August 10, 1821|
|Borders: TN, AR, IL, IA, KS, KY, NE and OK|
|MO Land Ownership Maps|
|MO Maps & Atlases|
|MO Birth, Marriage & Deaths|
|MO Military Databases|
|MO Record Collections|
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Today’s Missouri counties did not always exist in the present form. They went through many different changes in the space of a few short years.
Missouri Territorial Counties
The Missouri Territory was created on June 4, 1812. There were originally 5 Missouri counties when it was first organized as the Missouri Territory in 1812.
The State of Missouri entered the union as the 24th state on August 10, 1821.
Missouri Counties Today
Fun Facts about Missouri Counties
Counties by Year
- Cape Girardeau, New Madrid, St. Charles, St. Louis and St. Genevieve Counties was the original 5 counties created on October 1, 1812.
- Saint Louis City was the last county created on August 22, 1876.
County Size Facts
- Texas County (1,179 sq mi) is the largest county in Missouri.
- Worth County (266 sq mi) is the smallest county in Missouri.
County Population Facts
- Worth County (2,171) is the least populated county in Missouri.
- Saint Louis County (1,000,438) is the most populated county in Missouri.
Missouri City Facts
Missouri’s 10 largest cities (2020) are:
- Kansas City (487,816) is in Jackson, Platte, Cass and Clay Counties
- St. Louis (314,627) is in no county, its an none independent city.
- Springfield (174,607) is in Greene County
- Columbia (130,752) is in Boone County
- Independence (118,497) is in Jackson County
- Lee’s Summit (97,743) is in Jackson County
- O’Fallon (91,552) is in St. Charles County
- St. Joseph (77,248) is in Buchanan County
- St. Charles (71,685) is in St. Charles County
- St. Peter’s (61,769) is in St. Charles County
Boundary Changes of Missouri Counties from 1804-1889
This Interactive Map of Missouri Counties show the historical boundaries, names, organization, and attachments of every county, extinct county and unsuccessful county proposal from 1804 to 1889.
List of Missouri Counties
|County||Created||Created From||Named For||County Seat||Notes|
List of Old Former / Extinct Missouri Counties
Missouri contains some counties that no longer exist because they were discontinued, renamed or merged with another county. These are important for genealogy research purposes.
The below counties formerly within the area of the State of Missouri no longer exist:
- Clark County, Missouri: Renamed Cleveland County in 1885
- Decatur County, Missouri: Formed in 1841 as Ozark, renamed in 1843 to Decatur, renamed back to Ozark in 1845
- Dodge County, Missouri: Formed in 1849. Abolished in 1853
- Hempstead County, Missouri: Formed in 1818 from New Madrid County. Abolished in 1819; became part of the Arkansas Territory
- Lillard County, Missouri: Formed in 1821 from Cooper County; Abolished in 1825; divided into Jackson and LaFayette Counties
- Lawrence County, Missouri: Formed in 1815 from New Madrid County. Abolished in 1819; became part of the Arkansas Territory
- Kinderhook County, Missouri: Formed in1841 from Benton, Pulaski and Morgan Counties, renamed in 1843 to Camden County
- Niangua County, Missouri: Formed in1841 from Polk County, renamed in 1844 to Dallas County
- Seneca County, Missouri: Formed in 1847 from Newton County; renamed to McDonald County in 1849
- Van Buren County, Missouri: Formed as Van Buren, renamed to Cass County in 1849
COUNTY County, Missouri
Created on DATE from LAND. COUNTY County was renamed to COUNTY County on November 7, 1907.