In 1802, Spain returned most of the land to France, but keeping title to about 7,500 square miles. In 1803, most of the land formodern day Kansas was acquired by the United States from France as part of the 828,000 square mileLouisiana Purchase for 2.83cents peracre.
When the first counties were created by the Kansas legislature in 1855, the territory within the present limits of the county was attached toRiley County for all revenue and judicial purposes. Subsequently, Clay was attached toGeary County. In 1857, Clay was created and named in honor of the famous American statesmanHenry Clay,[4] a member of theUnited States Senate fromKentucky andUnited States Secretary of State in the 19th century.
In 2010, theKeystone-Cushing Pipeline (Phase II) was constructed north to south through Clay County, with much controversy over tax exemption and environmental concerns (if a leak ever occurs).[5][6] A pumping station named Riley was built along the pipeline.
According to theU.S. Census Bureau, the county has a total area of 656 square miles (1,700 km2), of which 645 square miles (1,670 km2) is land and 10 square miles (26 km2) (1.6%) is water.[7]
U.S. Decennial Census[10] 1790-1960[11] 1900-1990[12] 1990-2000[13] 2010-2020[1]
As of the2000 census,[14] there were 8,822 people, 3,617 households, and 2,517 families residing in the county. Thepopulation density was 14 people per square mile (5.4 people/km2). There were 4,084 housing units at an average density of 6 per square mile (2.3/km2). Theracial makeup of the county was 97.72%White, 0.57%Black orAfrican American, 0.41%Native American, 0.15%Asian, 0.26% from other races, and 0.90% fromtwo or more races.Hispanic orLatino people of any race were 0.83% of the population.
There were 3,617households, out of which 30.50% had children under the age of 18 living with them, 59.90% weremarried couples living together, 6.10% had a female householder with no husband present, and 30.40% were non-families. 27.70% of all households were made up of individuals, and 15.40% had someone living alone who was 65 years of age or older. The average household size was 2.39 and the average family size was 2.91.
In the county, the population was spread out, with 24.90% under the age of 18, 6.70% from 18 to 24, 23.90% from 25 to 44, 23.70% from 45 to 64, and 20.80% who were 65 years of age or older. The median age was 41 years. For every 100 females there were 99.10 males. For every 100 females age 18 and over, there were 95.60 males.
Themedian income for a household in the county was $33,965, and the median income for a family was $41,103. Males had a median income of $28,817 versus $17,760 for females. Theper capita income for the county was $17,939. About 6.80% of families and 10.10% of the population were below thepoverty line, including 14.60% of those under age 18 and 8.60% of those age 65 or over.
Like all of Kansas outside the eastern cities, Clay County is overwhelmingly Republican. WhenLyndon B. Johnson became in 1964 the last Democrat to carry the state's electoral votes, Clay County was his weakest in the state, giving over 62 percent of its votes toBarry Goldwater. The solitary Democrat to win a majority of Clay County's votes has beenWilliam Jennings Bryan in 1896, althoughWoodrow Wilson in a four-way race in 1912, andFranklin D. Roosevelt in 1932 both obtained slim pluralities. Roosevelt in 1936, when he lost to KansanAlf Landon by eighty-four votes, remains the last Democrat to win forty percent of the county's vote, andJimmy Carter in 1976 is the last to pass thirty percent.
Clay County is divided into eighteentownships. The city ofClay Center is consideredgovernmentally independent and is excluded from the census figures for the townships. In the following table, the population center is the largest city (or cities) included in that township's population total, if it is of a significant size.
Two formerKansas Governors resided in Clay County.George Docking was the 35th Governor, serving from January 14, 1957, until January 9, 1961.[18]William H. Avery was the 37th Governor, from January 11, 1965, until January 9, 1967.[19]