Rock County, Wisconsin

History

Rock County was created as a territorial county on December 7, 1836, from Milwaukee County and fully organized February 19, 1839. The county is named for the Rock River, which bisects the county from north to south.

Geography

According to the U.S. Census Bureau, the county has a total area of 726 sqmi, of which 718 sqmi is land and 8.0 sqmi (1.1%) is water.

Cook Memorial Arboretum, a natural area with birding and nature trails, is located northwest of Janesville. It is owned by the Janesville School District.

Transportation

Major highways

• [[File:I-39.svg|20px]] Interstate 39
• [[File:I-43.svg|20px]] Interstate 43
• [[File:I-90.svg|20px]] Interstate 90
• [[File:US 12.svg|20px]] U.S. Highway 12
• [[File:US 14.svg|20px]] U.S. Highway 14
• [[File:US 51.svg|20px]] U.S. Highway 51
• [[File:WIS 11.svg|20px]] Highway 11
• [[File:WIS 26.svg|20px]] Highway 26
• [[File:WIS 59.svg|20px]] Highway 59
• [[File:WIS 67.svg|20px]] Highway 67
• [[File:WIS 81.svg|20px]] Highway 81
• [[File:WIS 89.svg|20px]] Highway 89
• [[File:WIS 104.svg|20px]] Highway 104
• [[File:WIS 138.svg|20px]] Highway 138
• [[File:WIS 140.svg|20px]] Highway 140
• [[File:WIS 213.svg|20px]] Highway 213

Railroads

• Canadian Pacific
• Union Pacific
• Wisconsin and Southern Railroad

Buses

• Beloit Transit
• Janesville Transit System

Airport

Southern Wisconsin Regional Airport (KJVL) serves Rock County and the surrounding communities.

Adjacent counties

• Green County – west
• Dane County – north
• Jefferson County – northeast
• Walworth County – east
• Boone County, Illinois – south
• Winnebago County, Illinois – south

Demographics

|align-fn=center 1790–1960 1900–1990 1990–2000 2010 2020

2020 census

As of the 2020 census, the population was 163,687 and the median age was 40.3 years. 22.9% of residents were under the age of 18 and 17.6% of residents were 65 years of age or older. For every 100 females there were 97.5 males, and for every 100 females age 18 and over there were 95.1 males age 18 and over.

The population density was 227.9 /mi2, and there were 70,068 housing units at an average density of 97.6 /mi2.

The racial makeup of the county was 81.3% White, 5.1% Black or African American, 0.5% American Indian and Alaska Native, 1.3% Asian,

80.0% of residents lived in urban areas, while 20.0% lived in rural areas.

There were 65,937 households in the county, of which 29.6% had children under the age of 18 living in them. Of all households, 46.1% were married-couple households, 18.6% were households with a male householder and no spouse or partner present, and 26.1% were households with a female householder and no spouse or partner present. About 28.3% of all households were made up of individuals and 12.0% had someone living alone who was 65 years of age or older.

Of those housing units, 5.9% were vacant. Among occupied housing units, 69.0% were owner-occupied and 31.0% were renter-occupied. The homeowner vacancy rate was 1.0% and the rental vacancy rate was 4.8%.

2010 census

As of the 2010 census, there were 160,331 people residing in the county.

2000 census

As of the 2000 census, there were 152,307 people, 58,617 households, and 40,387 families residing in the county. The population density was 211 /mi2. There were 62,187 housing units at an average density of 86 /mi2.

The racial makeup of the county was 91.01% white, 4.63% black or African American, 0.28% Native American, 0.78% Asian, 0.04% Pacific Islander, 1.77% from other races, and 1.50% from two or more races. 3.91% of the population were Hispanic or Latino of any race. 32.8% were of German, 13.0% Norwegian, 10.1% Irish, 7.5% English and 5.5% American ancestry.

There were 58,617 households, out of which 33.60% had children under the age of 18 living with them, 53.50% were married couples living together, 10.90% had a female householder with no husband present, and 31.10% were non-families. 25.10% of all households were made up of individuals, and 9.70% had someone living alone who was 65 years of age or older. The average household size was 2.54 and the average family size was 3.03.

In the county, the population was spread out, with 26.50% under the age of 18, 8.60% from 18 to 24, 29.80% from 25 to 44, 22.30% from 45 to 64, and 12.70% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 97.00 males. For every 100 females age 18 and over, there were 94.10 males.

Communities

Cities

• Beloit
• Brodhead (mostly in Green County)
• Edgerton (partly in Dane County)
• Evansville
• Janesville (County seat)
• Milton

Villages

• Clinton
• Orfordville
• Footville

Towns

• Avon
• Beloit
• Bradford
• Center
• Clinton
• Fulton
• Harmony
• Janesville
• Johnstown
• La Prairie
• Lima
• Magnolia
• Milton
• Newark
• Plymouth
• Porter
• Rock
• Spring Valley
• Turtle
• Union

Census-designated places

• Fulton
• Hanover
• Shopiere

Unincorporated communities

• Afton
• Anderson
• Avalon
• Avon
• Belcrest
• Bergen
• Cainville
• Center
• Charlie Bluff
• Cooksville
• Coopers Shores
• Crestview
• Emerald Grove
• Fairfield (partial)
• Foxhollow
• Indianford
• Johnstown
• Johnstown Center
• Koshkonong (partial)
• Leyden
• Lima Center
• Magnolia
• Mallwood
• Maple Beach
• Newark
• Newville
• Porters
• Stebbinsville
• Tiffany
• Union
• Victory Heights

Ghost towns/neighborhoods

• Fellows
• Jefferson Prairie Settlement

Politics

Since 1988, Rock County has consistently voted for the Democratic candidate in every Presidential election. In 2024, Kamala Harris carried the county by the smallest margin of victory since Michael Dukakis in 1988.

Education

School districts include:

• Albany School District
• Beloit School District
• Beloit Turner School District
• Brodhead School District
• Clinton Community School District
• Delavan-Darien School District
• Edgerton School District
• Evansville Community School District
• Fort Atkinson School District
• Janesville School District
• Milton School District
• Oregon School District
• Parkview School District
• Stoughton Area School District
• Whitewater School District

There is a state-operated school, Wisconsin School for the Blind and Visually Impaired.

References

References

1. "2020 Decennial Census: Rock County, Wisconsin". U.S. Census Bureau.
2. "Find a County". National Association of Counties.
3. (2007). "Wisconsin: Individual County Chronologies". [[Newberry Library.
4. "[http://www.wisconsinhistory.org/dictionary/index.asp?action=view&term_id=3693&keyword=wisconsin Rock County, origin of place name]" ''Dictionary of Wisconsin History''.
5. (August 22, 2012). "2010 Census Gazetteer Files". United States Census Bureau.
6. Great Wisconsin Birding & Nature Trail. [http://www.wisconsinbirds.org/trail/sites/Cook.htm Cook Memorial Arboretum].
7. "Population and Housing Unit Estimates Tables". United States Census Bureau.
8. "U.S. Decennial Census". United States Census Bureau.
9. "Historical Census Browser". University of Virginia Library.
10. (March 27, 1995). "Population of Counties by Decennial Census: 1900 to 1990". United States Census Bureau.
11. (April 2, 2001). "Census 2000 PHC-T-4. Ranking Tables for Counties: 1990 and 2000". United States Census Bureau.
12. "State & County QuickFacts". United States Census Bureau.
13. (2021). "2020 Decennial Census Demographic Profile (DP1)".
14. (2021). "2020 Decennial Census Redistricting Data (Public Law 94-171)".
15. (2023). "2020 Decennial Census Demographic and Housing Characteristics (DHC)".
16. "U.S. Census website". [[United States Census Bureau]].
17. Leip, David. "Dave Leip's Atlas of U.S. Presidential Elections".
18. "2020 census - school district reference map: Rock County, WI". [[U.S. Census Bureau]].