Johnson County
County
Former Johnson County Courthouse in Olathe (2009). It opened in 1952, closed in 2020, then demolished in 2021 after a new courthouse was finished.[1][2]
Location within the U.S. state of Kansas
Kansas's location within the U.S.
Coordinates: 38°52′N 94°52′W / 38.867°N 94.867°W / 38.867; -94.867
Country	United States
State	Kansas
Founded	August 25, 1855
Named for	Thomas Johnson
Seat	Olathe
Largest city	Overland Park
Area
• Total	480 sq mi (1,200 km2)
• Land	473 sq mi (1,230 km2)
• Water	6.5 sq mi (17 km2)  1.4%
Population  (2020)[3]
• Total	609,863
• Estimate  (2021)[4]	613,219
• Density	1,289.4/sq mi (497.8/km2)
Time zone	UTC−6 (Central)
• Summer (DST)	UTC−5 (CDT)
Congressional district	3rd
Website	jocogov.org

Johnson County is a county in the U.S. state of Kansas, along the border of the state of Missouri. Its county seat is Olathe.^[5] As of the 2020 census, the population was 609,863, the most populous county in Kansas.^[3] The county was named after Thomas Johnson, a Methodist missionary who was one of the state's first settlers. Largely suburban, the county contains a number of suburbs of Kansas City, Missouri, including Overland Park, a principal city of and second most populous city in the Kansas City Metropolitan Area.^[6][7]

History

This was part of the large territory of the Osage people, who occupied lands up to present-day Saint Louis, Missouri. After the Indian Removal, the United States government reserved much of this area as Indian territory for a reservation for the Shawnee people, who were relocated from east of the Mississippi River in the upper Midwest.

The Santa Fe Trail and Oregon–California Trail, which pass through nearby Independence, Missouri, also passed through the county. Johnson County was established in 1855 as one of the first counties in the newly organized Kansas Territory; it was named for American missionary Thomas Johnson.^[8] The renowned gunfighter Wild Bill Hickok settled for a time in the county, becoming constable of Monticello Township in 1858.

Johnson County was the site of many battles between abolitionists and pro-slavery advocates during the period of Bleeding Kansas, prior to the residents voting on whether slavery would be allowed in the territory. In 1862 during the American Civil War, Confederate guerrillas from nearby Missouri, led by William Quantrill, raided the Johnson County communities of Olathe and Spring Hill. They killed half a dozen men and destroyed numerous homes and businesses.^[9]

The county was largely rural until the early 20th century, when housing subdivisions were developed in the northeastern portion of the county adjacent to Kansas City, Missouri. Developer J. C. Nichols spurred the boom in 1914 when he built the Mission Hills Country Club to lure upscale residents who previously had been reluctant to move from Missouri to Kansas.^[10] Suburban development continued at a steady pace until the close of World War II.

Following the war, the pace of development exploded, triggered by the return of veterans in need of housing, construction of highways that facilitated commuting from suburbs, and the pent-up demand for new housing. The US Supreme Court ruling in Brown v. Board of Education (1954) ruled that segregation of public schools was unconstitutional. Integration of public schools in Kansas City, Missouri, resulted in many white families leaving the inner city, resulting in increased migration to the county for new housing and what were considered higher quality public schools, generally an indicator of higher economic status. From the mid-1980s, the pace of growth increased significantly, with the county adding 100,000 residents each decade between the 1990 census and 2010 census.

The 1952 Johnson County Courthouse was closed in 2020, then demolished in 2021.^[1] It was replaced by a seven-story courthouse in 2021 after over two years of construction. This new courthouse is the county's fourth building.^[2]

Geography

According to the United States Census Bureau, the county has a total area of 480 square miles (1,200 km²), of which 473 square miles (1,230 km²) is land and 6.5 square miles (17 km²) (1.4%) is water.^[11]

Topography

The natural topography of the county consists of gently rolling terrain. The Kansas River forms a portion of the northwest boundary of the county. The elevation generally increases from north to south as the distance from the Kansas and Missouri rivers increases.

Watersheds and streams

The county is drained by the watersheds of the Kansas, Blue, and Marais des Cygnes, all of which are part of the Missouri River watershed. Located in northeastern Kansas, the county receives plentiful rainfall. The county contains numerous small streams, including Kill Creek, Mill Creek, Turkey Creek, Indian Creek, Brush Creek, Tomahawk Creek, the Blue River, Bull Creek and Little Bull Creek.

Kill Creek begins in the southwest portion of the county and flows northward into the Kansas River at De Soto. Mill Creek begins in the central portion of the county in Olathe, flowing northward it empties into the Kansas River at Shawnee. Turkey Creek and Brush Creek each begin in northeast Johnson County. Turkey Creek flows northeastward into Wyandotte County and joins the Kansas River just before its confluence with the Missouri River at Kaw Point. Brush Creek flows east-northeastward through Prairie Village and Mission Hills, entering Kansas City, Missouri, within the median of Ward Parkway and passing the Country Club Plaza before emptying into the Blue River east of the Country Club Plaza and north of Swope Park. Indian Creek begins in the southern portion of Olathe and Tomahawk Creek begins in south Overland Park. Each flows northeastward meeting in Leawood, where the stream retains the name of Indian Creek, just before crossing the state line and entering the Blue River in Kansas City, Missouri. The Blue River begins in rural southern Johnson County and flows north-northeastward through the southeastern portion of the county and crossing the state line just east of the intersection of 151st Street and Kenneth Road in southern Overland Park. The Blue River flows through southern and eastern Kansas City before joining the Missouri River. Bull Creek and Little Bull Creek begin in rural southwestern Johnson County and flow southward where they enter Hillsdale Lake before continuing into Miami County, eventually joining the Marais des Cygnes at Paola.

Flora and fauna

The county consists primarily of prairie grassland with corridors of forested areas along streams and rivers.

Adjacent counties

• Wyandotte County (north)
• Jackson County, Missouri (east)
• Cass County, Missouri (southeast)
• Miami County (south)
• Franklin County (southwest)
• Douglas County (west)
• Leavenworth County (northwest)

Demographics

Johnson County (county code JO) is included in the Kansas City metropolitan area. The county has the highest median household income at $81,121 in 2017 and the highest per-capita income in Kansas, with the 19th highest median household income in 2000 and the 46th highest per-capita income in 2005. In 2010, Money magazine, in its list of the '100 Best Cities in the United States' in which to live, ranked Overland Park 7th (ranked 6th in 2006 and 9th in 2008) and Shawnee 17th (ranked 39th in 2008).^[17] In 2008 the same magazine also ranked Olathe 11th.^[18]

2010

As of the 2010 census, there were 544,179 people, 210,278 households, and 143,509 families residing in the county. The population density was 1,150 inhabitants per square mile (440/km²). There were 226,571 housing units at an average density of 381 per square mile (147/km²). The racial makeup of the county was 86.0% White, 4.2% Asian, 4.3% Black or African American, 0.4% Native American, 0.01% Pacific Islander, 1.55% from other races, and 2.5% from two or more races. Hispanic or Latino of any race were 7.2% of the population. 30.6% identified as of German, 16.8% Irish, 13.6% English and 5.7% American ancestry.^[19]

There were 210,278 households, out of which 34.6% had children under the age of 18 living with them, 56.1% were married couples living together, 8.4% had a female householder with no husband present, and 31.8% were non-families. 25.9% of all households were made up of individuals, and 7.8% had someone living alone who was 65 years of age or older. The average household size was 2.51 and the average family size was 3.05.^[19]

In the county, the population was spread out, with 26.3% under the age of 18, 7.60% from 18 to 24, 32.80% from 25 to 44, 22.50% from 45 to 64, and 10.9% who were 65 years of age or older. The median age was 36.4 years. 48.8% of the population were males and 51.2% of the population were females.

The median income for a household in the county was $73,733, and the median income for a family was $90,380. Males had a median income of $61,346 versus $43,785 for females. The per capita income for the county was $37,882. About 3.6% of families and 5.5% of the population were below the poverty line, including 7.1% of those under age 18 and 4.9% of those age 65 or over.^[19]

2000

As of the census of 2000, there were 451,086 people, 174,570 households, and 121,675 families residing in the county. The population density was 365/km² (950/sq mi). There were 181,612 housing units at an average density of 147/km² (380/sq mi). The racial makeup of the county was 91.11% White, 2.61% Black or African American, 0.33% Native American, 2.83% Asian, 0.03% Pacific Islander, 1.55% from other races, and 1.54% from two or more races. 3.98% of the population were Hispanic or Latino of any race.

There were 174,570 households, out of which 36.00% had children under the age of 18 living with them, 59.20% were married couples living together, 7.80% had a female householder with no husband present, and 30.30% were non-families. 24.50% of all households were made up of individuals, and 6.70% had someone living alone who was 65 years of age or older. The average household size was 2.56 and the average family size was 3.09.

In the county the population was spread out, with 27.10% under the age of 18, 7.60% from 18 to 24, 32.80% from 25 to 44, 22.50% from 45 to 64, and 10.00% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 95.50 males. For every 100 females age 18 and over, there were 92.00 males.

The median income for a household in the county was $61,455, and the median income for a family was $72,987. Males had a median income of $49,790 versus $32,145 for females. The per capita income for the county was $30,919. 3.40% of the population and 2.10% of families were below the poverty line. Out of the total population, 3.30% of those under the age of 18 and 3.60% of those 65 and older were living below the poverty line.

Government

Laws

Johnson County was a prohibition, or "dry", county until the Kansas Constitution was amended in 1986 and voters approved the sale of alcoholic liquor by the individual drink, with a 30% food sales requirement.^[20]

The county voted "No" on the 2022 Kansas Value Them Both Amendment, an anti-abortion ballot measure, by 68% to 32%, outpacing its support of Joe Biden during the 2020 presidential election.^[21]

Federal representation