Clay County, Illinois
Clay County: county in Illinois, United States.
About
Clay County is a county located in the U.S. state of Illinois. As of the 2010 census, the population was 13,815 and a population density of 11 people per km². After 10 years in 2020 county had an estimated population of 13,079 inhabitants. Its county seat is Louisville. The county was created 202 years ago in 1823.
County Snapshot
Clay County at a glance
Clay County currently has 2 quality-checked populated place pages linked on MapSof, making it easier to jump from the county overview into local city pages.
Mapped populated places
2
These counts use a stricter populated-place filter so the main lists stay focused on real city and town pages.
Illinois counties
102
Open related pagesLargest city
FloraPopulation 4,831
Top linked places
Quick Facts about Clay County
| Population | 13,079 (2020) |
| Country | United States of America |
| State | Illinois (United States) |
| Different from | Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County, Clay County |
| Area | 1217 km2 |
| Water as percent of area | 0.3% |
| Land as percent of area | 99.7% |
| Latitude & Longitude | 38.7542,-88.4902 |
| Named for | Henry Clay |
| Capital | Louisville |
| Establishment | January 01, 1824 |
| Time Zone | America/Chicago |
| Local time | 09:10:25 (23rd September 2026) |
| Density | 11 Pop. per km² as of 2020 |
| Population growth | -5.33% (2010-2020) |
| Weather | 71℉ Cloudy 7-days weather |
Geography
Clay County is located at 38°45'15"N 88°29'25"W (38.7541600, -88.4901900). It has 4 neighbors: Fayette County, Jasper County, Marion County and Wayne County.
Clay County map
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The largest city of Clay County is Flora with a population of 4,831. Other cities include and Louisville population 1,087. See all Clay County cities & populated places.
Clay County Populated Places
Cities, towns, neighborhoods & other populated places in Clay County.
| City Name | Population | Title |
|---|---|---|
| Flora | 4,831 | City in Illinois |
| Louisville | 1,087 | Village in Illinois |
Weather
Cloudy, with a high near 71. North northeast wind 7 to 10 mph.
7-Day ForecastOfficial website of Clay County
Official WebsiteDemographics
According to census records, the population of Clay County decreased by 5.33% in 10 years.
| Year | Population | % Change | Method |
|---|---|---|---|
| 2010 | 13,815 | - | census |
| 2011 | 13,725 | -0.65% | estimation process |
| 2012 | 13,714 | -0.08% | estimation process |
| 2013 | 13,554 | -1.17% | estimation process |
| 2014 | 13,445 | -0.8% | estimation process |
| 2015 | 13,401 | -0.33% | estimation process |
| 2016 | 13,314 | -0.65% | estimation process |
| 2017 | 13,270 | -0.33% | estimation process |
| 2018 | 13,266 | -0.03% | estimation process |
| 2019 | 13,184 | -0.62% | estimation process |
| 2020 | 13,079 | -0.8% | estimation process |
People born in Clay County (1)
novelist David Niall Wilson was born in Clay County
Other places with the same name (17)
- Clay County, Missouri county in North Carolina, United States. with a population of 253,463 people.
- Clay County, Florida county in Florida, United States. with a population of 221,770 people.
- Clay County, Minnesota county in Minnesota, United States. with a population of 64,690 people.
- Clay County, Indiana county in Indiana, United States. with a population of 26,246 people.
- Clay County, Kentucky county in Kentucky, United States. with a population of 19,631 people.
- Clay County, Mississippi county in Mississippi, United States. with a population of 19,352 people.
- Clay County, Iowa county in Iowa, United States. with a population of 15,976 people.
- Clay County, Arkansas county in Arkansas, United States. with a population of 14,375 people.
- Clay County, South Dakota county in Clay County South Dakota, United States. with a population of 14,246 people.
- Clay County, Alabama county in Alabama, United States. with a population of 13,112 people.
- Clay County, North Carolina county in North Carolina, United States. with a population of 11,505 people.
- Clay County, Texas county in Texas, United States. with a population of 10,550 people.
- Clay County, West Virginia county in West Virginia, United States. with a population of 8,341 people.
- Clay County, Kansas county in Kansas, United States. with a population of 8,025 people.
- Clay County, Tennessee county in Tennessee, United States. with a population of 7,629 people.
- Clay County, Nebraska county in Nebraska, United States. with a population of 6,216 people.
- Clay County, Georgia county in Georgia, United States. with a population of 2,866 people.
Illinois Other Counties (more counties)
| County Name | Population | Title |
|---|---|---|
| Cook County | 5,108,284 | County in Illinois, United States |
| Chicago | 2,677,643 | The third most populous city in the United States and the center of the Chicago metropolitan area. |
| DuPage County | 917,481 | County in Illinois, United States |
| Lake County | 693,593 | County in Oregon, United States |
| Will County | 688,726 | County in Illinois, United States |
| Kane County | 531,010 | County in southern Utah, United States |
| McHenry County | 305,888 | County in Illinois, United States |
| Winnebago County | 281,295 | County in Illinois, United States |
| Madison County | 262,635 | County in Montana, United States |
| Saint Clair County | 258,046 | The County of St. |
| Champaign County | 209,192 | County in Illinois, United States |
| Aurora | 196,383 | The second most populous city in Illinois. |
| Sangamon County | 193,882 | County in Illinois, United States |
| Peoria County | 177,652 | County in Illinois, United States of America |
| McLean County | 171,256 | County in North Dakota, United States |
| Naperville | 147,986 | The second most populous city in Illinois. |