Iowa County, Iowa

Iowa County, Iowa
County
The Iowa County Courthouse in Marengo
Location within the U.S. state of Iowa
Coordinates: 41°41′02″N 92°03′33″W / 41.683918°N 92.059123°W / 41.683918; -92.059123
Country United States
State Iowa
FoundedFebruary 17, 1843 (created)
July 1, 1845 (organized)
Named afterIowa River
SeatMarengo
Largest cityWilliamsburg
Area
 • Total
587.492 sq mi (1,521.60 km2)
 • Land586.455 sq mi (1,518.91 km2)
 • Water1.037 sq mi (2.69 km2)  0.18%
Population
 (2020)
 • Total
16,662
 • Estimate 
(2024)
16,423
 • Density28.411/sq mi (10.970/km2)
Time zoneUTC−6 (Central)
 • Summer (DST)UTC−5 (CDT)
Area code319
Congressional district1st
Websiteiowacounty.iowa.gov
  • Iowa county number 48[1]

Iowa County is a county in the U.S. state of Iowa. As of the 2020 census, the population was 16,662,[2] and was estimated to be 16,423 in 2024.[3] The county seat is Marengo and the largest city is Williamsburg.[4] Iowa County is one of seven counties in the United States to share the same name as the state in which they are located. The other six counties are Arkansas County, Hawaii County, Idaho County, New York County, Oklahoma County, and Utah County.[5]

History

Iowa County was formed on February 17, 1843.[6] It was named for the Iowa River, which flows through the county. The first courthouse was a log cabin built in 1847. It was rented by the county until 1850 when a second courthouse was completed. In 1861 construction of a third courthouse was begun. The current courthouse was built in 1892 after the county had outgrown the previous one.

Iowa County is home to the Amana Colonies, a group of settlements of German Pietists comprising seven villages. Calling themselves the Ebenezer Society or the Community of True Inspiration (German: die Gemeinde der wahren Inspiration), they first settled in New York state near Buffalo in what is now West Seneca. However, in order to live out their beliefs in more isolated surroundings they moved west, to Iowa County in 1855, living a communal life until the mid-1930s. Today, Amana is a major tourist attraction known mainly for its restaurants and craft shops, and the colonies as a whole have been listed as a National Historic Landmark since 1965.

Geography

According to the United States Census Bureau, the county has a total area of 587.492 square miles (1,521.60 km2), of which 586.455 square miles (1,518.91 km2) is land and 1.037 square miles (2.69 km2) (0.18%) is water.[7] It is the 26th largest county in Iowa by total area.[8] The county is intersected by the Iowa River and the north fork of the English River.[9]

Major highways

Adjacent counties

Demographics

Historical population
CensusPop.Note%±
1850822—
18608,029876.8%
187016,644107.3%
188019,22115.5%
189018,270−4.9%
190019,5447.0%
191018,409−5.8%
192018,6001.0%
193017,332−6.8%
194017,016−1.8%
195015,835−6.9%
196016,3963.5%
197015,419−6.0%
198015,4290.1%
199014,630−5.2%
200015,6717.1%
201016,3554.4%
202016,6621.9%
2024 (est.)16,423[10] −1.4%
U.S. Decennial Census[11]
1790–1960[12] 1900–1990[13]
1990–2000[14] 2010–2020[3]

As of the second quarter of 2025, the median home value in Iowa County was $213,544.[15]

As of the 2024 American Community Survey, there are 6,909 estimated households in Iowa County with an average of 2.34 persons per household. The county has a median household income of $71,223. Approximately 8.9% of the county's population lives at or below the poverty line. Iowa County has an estimated 65.3% employment rate, with 24.8% of the population holding a bachelor's degree or higher and 95.5% holding a high school diploma.[3] There were 7,369 housing units at an average density of 12.57 per square mile (4.9/km2).

The top five reported languages (people were allowed to report up to two languages, thus the figures will generally add to more than 100%) were English (97.3%), Spanish (1.4%), Indo-European (0.7%), Asian and Pacific Islander (0.5%), and Other (0.1%).

The median age in the county was 42.4 years.

Iowa County, Iowa – racial and ethnic composition
Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race.
Race / ethnicity (NH = non-Hispanic) Pop. 1980[16] Pop. 1990[17] Pop. 2000[18] Pop. 2010[19] Pop. 2020[20]
White alone (NH) 15,305
(99.20%)		 14,539
(99.38%)		 15,390
(98.21%)		 15,818
(96.72%)		 15,394
(92.39%)
Black or African American alone (NH) 4
(0.03%)		 7
(0.05%)		 25
(0.16%)		 53
(0.32%)		 111
(0.67%)
Native American or Alaska Native alone (NH) 7
(0.05%)		 10
(0.07%)		 10
(0.06%)		 14
(0.09%)		 29
(0.17%)
Asian alone (NH) 38
(0.25%)		 34
(0.23%)		 47
(0.30%)		 54
(0.33%)		 84
(0.50%)
Pacific Islander alone (NH) — — 3
(0.02%)		 2
(0.01%)		 1
(0.01%)
Other race alone (NH) 33
(0.21%)		 1
(0.01%)		 4
(0.03%)		 9
(0.06%)		 57
(0.34%)
Mixed race or multiracial (NH) — — 40
(0.26%)		 98
(0.60%)		 491
(2.95%)
Hispanic or Latino (any race) 42
(0.27%)		 39
(0.27%)		 152
(0.97%)		 307
(1.88%)		 495
(2.97%)
Total 15,429
(100.00%)		 14,630
(100.00%)		 15,671
(100.00%)		 16,355
(100.00%)		 16,662
(100.00%)

2020 census

As of the 2020 census, there were 16,662 people, 6,811 households, and 4,509 families residing in the county.[21] The population density was 28.41 inhabitants per square mile (11.0/km2). There were 7,341 housing units at an average density of 12.52 per square mile (4.8/km2). The racial makeup of the county was 93.45% White, 0.67% African American, 0.21% Native American, 0.56% Asian, 0.01% Pacific Islander, 1.34% from some other races and 3.76% from two or more races. Hispanic or Latino people of any race were 2.97% of the population.[22][23]

And 96.24% of residents reported being of one race. The median age was 42.6 years; 23.4% of residents were under the age of 18 and 19.8% were 65 years of age or older. For every 100 females there were 98.8 males, and for every 100 females age 18 and over there were 95.9 males age 18 and over.[24]

<0.1% of residents lived in urban areas, while 100.0% lived in rural areas.[25]

There were 6,811 households in the county, of which 28.9% had children under the age of 18 living in them. Of all households, 55.3% were married-couple households, 16.9% were households with a male householder and no spouse or partner present, and 21.6% were households with a female householder and no spouse or partner present. About 28.7% of all households were made up of individuals and 13.7% had someone living alone who was 65 years of age or older.[24]

There were 7,341 housing units, of which 6,811 were occupied; 7.2% were vacant. Among occupied housing units, 79.1% were owner-occupied and 20.9% were renter-occupied. The homeowner vacancy rate was 1.5% and the rental vacancy rate was 8.6%.[24]

2010 census

As of the 2010 census, there were 16,355 people, 6,677 households, and _ families residing in the county. The population density was 27.89 inhabitants per square mile (10.8/km2). There were 7,258 housing units at an average density of 12.38 per square mile (4.8/km2). The racial makeup of the county was 97.84% White, 0.35% African American, 0.17% Native American, 0.34% Asian, 0.01% Pacific Islander, 0.54% from some other races and 0.75% from two or more races. Hispanic or Latino people of any race were 1.88% of the population.

2000 census

As of the 2000 census, there were 15,671 people, 6,163 households, and 4,301 families residing in the county. The population density was 26.72 inhabitants per square mile (10.3/km2). There were 6,545 housing units at an average density of 11.16 per square mile (4.3/km2). The racial makeup of the county was 98.70% White, 0.17% African American, 0.06% Native American, 0.30% Asian, 0.03% Pacific Islander, 0.36% from some other races and 0.38% from two or more races. Hispanic or Latino people of any race were 0.97% of the population.

There were 6,163 households, out of which 32.80% had children under the age of 18 living with them, 60.10% were married couples living together, 6.60% had a female householder with no husband present, and 30.20% were non-families. 25.90% of all households were made up of individuals, and 12.50% had someone living alone who was 65 years of age or older. The average household size was 2.50 and the average family size was 3.03. In the county the population was spread out, with 26.40% under the age of 18, 6.30% from 18 to 24, 27.80% from 25 to 44, 22.40% from 45 to 64, and 17.10% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 95.00 males. For every 100 females age 18 and over, there were 93.20 males.

The median income for a household in the county was $41,222, and the median income for a family was $48,946. Males had a median income of $31,220 versus $24,652 for females. The per capita income for the county was $18,884. About 3.40% of families and 5.00% of the population were below the poverty line, including 4.50% of those under age 18 and 5.40% of those age 65 or over.

Politics

In the 2008 US presidential election, a nearly equal number of Iowa County voters voted for each major candidate, with Barack Obama winning the county by a narrow margin of 14 votes.[26]

In the 2012 US presidential election, Mitt Romney received 4,551 votes (51.8%).[27] In the 2016 US presidential election, Donald Trump received 5,193 votes (59.1%).[28] In the 2020 US presidential election, Donald Trump received 6,009 votes (61.8%).[29] In the 2024 US presidential election, Donald Trump received 6,068 votes (63.0%).

United States presidential election results for Iowa County, Iowa[30]
Year Republican Democratic Third party(ies)
No.  % No.  % No.  %
1896 2,391 53.78% 1,956 43.99% 99 2.23%
1900 2,336 52.70% 1,983 44.73% 114 2.57%
1904 2,303 52.81% 1,891 43.36% 167 3.83%
1908 2,230 52.58% 1,907 44.97% 104 2.45%
1912 1,237 30.76% 1,841 45.77% 944 23.47%
1916 2,484 57.90% 1,763 41.10% 43 1.00%
1920 4,892 69.92% 2,019 28.86% 86 1.23%
1924 3,549 51.91% 1,458 21.33% 1,830 26.77%
1928 4,091 56.85% 3,075 42.73% 30 0.42%
1932 2,628 35.04% 4,376 58.35% 495 6.60%
1936 3,360 43.57% 4,163 53.98% 189 2.45%
1940 4,696 55.33% 3,649 42.99% 143 1.68%
1944 3,959 53.94% 3,119 42.49% 262 3.57%
1948 3,659 52.44% 3,030 43.42% 289 4.14%
1952 5,625 67.27% 2,514 30.06% 223 2.67%
1956 4,875 62.68% 2,753 35.40% 149 1.92%
1960 4,944 63.47% 2,828 36.30% 18 0.23%
1964 2,828 39.82% 4,261 60.00% 13 0.18%
1968 4,133 58.12% 2,586 36.37% 392 5.51%
1972 4,202 60.34% 2,578 37.02% 184 2.64%
1976 3,926 52.98% 3,367 45.43% 118 1.59%
1980 4,153 55.21% 2,606 34.65% 763 10.14%
1984 4,352 60.02% 2,815 38.82% 84 1.16%
1988 3,247 48.57% 3,338 49.93% 100 1.50%
1992 2,656 38.13% 2,560 36.76% 1,749 25.11%
1996 3,042 43.24% 3,354 47.68% 639 9.08%
2000 3,894 52.53% 3,230 43.57% 289 3.90%
2004 4,544 53.75% 3,841 45.43% 69 0.82%
2008 4,188 48.99% 4,202 49.16% 158 1.85%
2012 4,569 51.53% 4,144 46.74% 153 1.73%
2016 5,205 58.46% 3,084 34.64% 615 6.91%
2020 6,009 61.68% 3,547 36.41% 186 1.91%
2024 6,068 62.95% 3,400 35.27% 171 1.77%

Communities

Cities

Census-designated places

Other unincorporated communities

  • Ambrose
  • Armah
  • Genoa Bluff
  • Holbrook
  • Koszta
  • Upper South Amana

Townships

Population ranking

Population rankings based on the 2020 census of Iowa County:

† county seat

Rank City/Town/etc. Municipal type Population
(2020 Census) 		Population
(2024 Estimate)
1 Williamsburg City 3,346 3,380
2 † Marengo City 2,435 2,415
3 North English (partially in Keokuk County) City 1,065 1,030
4 Victor (partially in Poweshiek County) City 875 852
5 Middle Amana CDP 543 739
6 Amana CDP 388 650
7 Ladora City 229 223
8 Parnell City 194 190
9 Homestead CDP 135 149
10 Millersburg City 135 135
11 Conroy CDP 252 128
12 South Amana CDP 165 126
13 High Amana CDP 113 80
14 East Amana CDP 64 53
15 West Amana CDP 140 45

Education

School districts include:[31]

See also

References

  1. ^ "Iowa County Names and Numbers". Iowa Department of Administrative Services. Retrieved February 5, 2026.
  2. ^ "Explore Census Data". United States Census Bureau. Retrieved February 5, 2026.
  3. ^ a b c "U.S. Census Bureau QuickFacts: Iowa County, Iowa". www.census.gov. Retrieved February 5, 2026.
  4. ^ "Find a County". National Association of Counties. Retrieved February 5, 2026.
  5. ^ Joseph Nathan Kane; Charles Curry Aiken (2005). The American Counties: Origins of County Names, Dates of Creation, and Population Data, 1950-2000. Scarecrow Press. ISBN 978-0-8108-5036-1.
  6. ^ "Iowa: Individual County Chronologies". publications.newberry.org. The Newberry Library. 2007. Retrieved February 5, 2026.
  7. ^ "2025 County Gazetteer Files – Iowa". United States Census Bureau. Retrieved February 5, 2026.
  8. ^ "U.S. Census Bureau QuickFacts: Iowa County, Iowa". www.census.gov. Retrieved February 5, 2026.
  9. ^ Ripley, George; Dana, Charles A., eds. (1879). "Iowa. II. An E. county of Iowa" . The American Cyclopædia.
  10. ^ "County Population Totals and Components of Change: 2020-2024". Retrieved July 24, 2025.
  11. ^ "U.S. Decennial Census". United States Census Bureau. Retrieved January 7, 2014.
  12. ^ "Historical Census Browser". University of Virginia Library. 2007. Archived from the original on December 12, 2009. Retrieved January 7, 2014.
  13. ^ Forstall, Richard L. (April 20, 1995). "Population of Counties by Decennial Census: 1900 to 1990". United States Census Bureau. Archived from the original on February 19, 1999. Retrieved January 7, 2014.
  14. ^ "Census 2000 PHC-T-4. Ranking Tables for Counties: 1990 and 2000" (PDF). United States Census Bureau. Archived (PDF) from the original on March 27, 2010. Retrieved January 7, 2014.
  15. ^ "County Median Home Price". National Association of Realtors. Retrieved February 5, 2026.
  16. ^ "Iowa County, Iowa — Population by Race". CensusScope. Retrieved February 5, 2026.
  17. ^ "1990 Census of Population: General Population Characteristics Iowa" (PDF). www.census.gov. October 6, 2022. p. 30. Retrieved February 5, 2026.
  18. ^ "P004: Hispanic or Latino, and Not Hispanic or Latino by Race – 2000: DEC Summary File 1 – Iowa County, Iowa". United States Census Bureau. Retrieved February 5, 2026.
  19. ^ "P2: Hispanic or Latino, and Not Hispanic or Latino by Race – 2010: DEC Redistricting Data (PL 94-171) – Iowa County, Iowa". United States Census Bureau. Retrieved February 5, 2026.
  20. ^ "P2: Hispanic or Latino, and Not Hispanic or Latino by Race – 2020: DEC Redistricting Data (PL 94-171) – Iowa County, Iowa". United States Census Bureau. Retrieved February 5, 2026.
  21. ^ "U.S. Census Bureau, Table P16: Household Type". United States Census Bureau. Retrieved February 5, 2026.
  22. ^ "How many people live in Iowa County, Iowa". USA Today. Retrieved January 21, 2026.
  23. ^ "2020 Decennial Census Redistricting Data (Public Law 94-171)". United States Census Bureau. 2021. Retrieved December 25, 2025.
  24. ^ a b c "2020 Decennial Census Demographic Profile (DP1)". United States Census Bureau. 2021. Retrieved December 25, 2025.
  25. ^ "2020 Decennial Census Demographic and Housing Characteristics (DHC)". United States Census Bureau. 2023. Retrieved December 25, 2025.
  26. ^ Local and National Election Results - Election Center 2008 [1], accessed June 16, 2012.
  27. ^ Lattman, Peter (2012). "Iowa". The New York Times.
  28. ^ "2016 Iowa Presidential Election Results". Politico. Axel Springer SE. December 13, 2016.
  29. ^ Vestal, Allan; Briz, Andrew; Choi, Annette; Jin, Beatrice; McGill, Andrew; Mihalik, Lily (January 6, 2021). "Iowa presidential results". Politico. Axel Springer SE.
  30. ^ Leip, David. "Dave Leip's Atlas of U.S. Presidential Elections". uselectionatlas.org. Retrieved April 26, 2018.
  31. ^ 2020 Census - School District Reference Map: Iowa County, IA (PDF) (Map). United States Census Bureau. January 15, 2021. Retrieved February 5, 2026. - Text list
Wikimedia Commons has media related to Iowa County, Iowa.
This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.