List of counties in Iowa
Encyclopedia
There are 99 counties in the U.S. state
of Iowa
. The first two counties, Des Moines County and Dubuque County, were created in 1834 when Iowa was still part of the Michigan Territory
. In preparation for Michigan's statehood, part of Michigan Territory was formed into Wisconsin Territory
in 1836. Two years later, the western portion was split off to become Iowa Territory
. The south-eastern part of Iowa Territory became Iowa, the 29th state in the union, on 28 December 1846, by which point 44 counties had been created. Counties continued to be created by the state government until 1857, when the last county, Humboldt County
, was created. One of the most significant days in Iowa county history was January 15, 1851, on which 49 counties were created.
The Iowa Constitution of 1857, which is still in effect today, states that counties must have an area of at least 432 square miles (1,118.9 km²), nor can any county be reduced below that size by boundary changes. However, exceptions to this rule were granted, as ten counties have areas below this size. (The table below shows land area, but the Constitution deals with total area.) The smallest county (Dickinson) has a land area of 381 sq mi (986.8 km²), while the largest (Kossuth) has an area 973sq mi (2,520 km²). Polk County is the most densely populated county at 657 persons/sq mi, and contains the state's capital and largest city, Des Moines
.
(FIPS) code, which is used by the United States government to uniquely identify counties, is provided with each entry. The FIPS code for each county links to census data for that county.
|}
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...
of Iowa
Iowa
Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...
. The first two counties, Des Moines County and Dubuque County, were created in 1834 when Iowa was still part of the Michigan Territory
Michigan Territory
The Territory of Michigan was an organized incorporated territory of the United States that existed from June 30, 1805, until January 26, 1837, when the final extent of the territory was admitted to the Union as the State of Michigan...
. In preparation for Michigan's statehood, part of Michigan Territory was formed into Wisconsin Territory
Wisconsin Territory
The Territory of Wisconsin was an organized incorporated territory of the United States that existed from July 3, 1836, until May 29, 1848, when an eastern portion of the territory was admitted to the Union as the State of Wisconsin...
in 1836. Two years later, the western portion was split off to become Iowa Territory
Iowa Territory
The Territory of Iowa was an organized incorporated territory of the United States that existed from July 4, 1838, until December 28, 1846, when the southeastern portion of the territory was admitted to the Union as the State of Iowa.-History:...
. The south-eastern part of Iowa Territory became Iowa, the 29th state in the union, on 28 December 1846, by which point 44 counties had been created. Counties continued to be created by the state government until 1857, when the last county, Humboldt County
Humboldt County, Iowa
-2010 census:The 2010 census recorded a population of 9,815 in the county, with a population density of . There were 4,684 housing units, of which 4,209 were occupied.-2000 census:...
, was created. One of the most significant days in Iowa county history was January 15, 1851, on which 49 counties were created.
The Iowa Constitution of 1857, which is still in effect today, states that counties must have an area of at least 432 square miles (1,118.9 km²), nor can any county be reduced below that size by boundary changes. However, exceptions to this rule were granted, as ten counties have areas below this size. (The table below shows land area, but the Constitution deals with total area.) The smallest county (Dickinson) has a land area of 381 sq mi (986.8 km²), while the largest (Kossuth) has an area 973sq mi (2,520 km²). Polk County is the most densely populated county at 657 persons/sq mi, and contains the state's capital and largest city, Des Moines
Des Moines, Iowa
Des Moines is the capital and the most populous city in the US state of Iowa. It is also the county seat of Polk County. A small portion of the city extends into Warren County. It was incorporated on September 22, 1851, as Fort Des Moines which was shortened to "Des Moines" in 1857...
.
County information
The number in the column headed "#" is the one used on the map from the National Atlas of the United States, shown on the left. The Federal Information Processing StandardFederal Information Processing Standard
A Federal Information Processing Standard is a publicly announced standardization developed by the United States federal government for use in computer systems by all non-military government agencies and by government contractors, when properly invoked and tailored on a contract...
(FIPS) code, which is used by the United States government to uniquely identify counties, is provided with each entry. The FIPS code for each county links to census data for that county.
|}
Former counties
The following counties no longer exist:- BancroftBancroft County, IowaBancroft County, Iowa was a county located in what today is the northern portion of Kossuth County. The county was established in 1851 by the Iowa General Assembly, but then abolished six years later in 1857 and the area joined to Kossuth County....
(1851–1855), merged with Kossuth CountyKossuth County, Iowa-2010 census:The 2010 census recorded a population of 15,543 in the county, with a population density of . There were 7,486 housing units, of which 6,697 were occupied.-2000 census:... - Cook (1836–1837), merged with Muscatine CountyMuscatine County, Iowa-2010 census:The 2010 census recorded a population of 42,745 in the county, with a population density of . There were 17,910 housing units, of which 16,412 were occupied.-2000 census:...
- CrockerCrocker County, IowaCrocker County is a defunct county in the U.S. state of Iowa. In 1870, the Iowa General Assembly created Crocker County from the southern part of Kossuth County. The county seat was located at Greenwood, Iowa...
(1870–1871), merged with Kossuth CountyKossuth County, Iowa-2010 census:The 2010 census recorded a population of 15,543 in the county, with a population density of . There were 7,486 housing units, of which 6,697 were occupied.-2000 census:... - Risley (1851–1853), formed Webster CountyWebster County, Iowa-2010 census:The 2010 census recorded a population of 38,013 in the county, with a population density of . There were 17,035 housing units, of which 15,580 were occupied.-2000 census:...
- Yell (1851–1853), formed Webster CountyWebster County, Iowa-2010 census:The 2010 census recorded a population of 38,013 in the county, with a population density of . There were 17,035 housing units, of which 15,580 were occupied.-2000 census:...