Rock Island County is a county located in the U.S. state of Illinois, bounded on the west by the Mississippi River. According to the 2020 census, it had a population of 144,672. Its county seat is Rock Island; its largest city is neighboring Moline. Rock Island County is one of the four counties that make up the Davenport–Moline–Rock Island, IA–IL Metropolitan Statistical Area.

History

Rock Island County was formed in 1831 out of Jo Daviess County. It was named for Rock Island, an island in the Mississippi River now known as Arsenal Island.Rock Island, the island, History: Introduction , US Army Corps of Engineers The Rock River (which the Sauk and Meskwaki peoples called Sinnissippi, meaning "rocky waters") flows from Whiteside County and points further east and north and joins the Mississippi River at Rock Island. The Sinnissippi Mounds, dating from the Hopewell period and on the National Register of Historic Places are upriver at Sterling in Whiteside County.

Geography According to the U.S. Census Bureau, the county has a total area of , of which is land and (5.2%) is water.

Climate and weather

In recent years, average temperatures in the county seat of Rock Island have ranged from a low of in January to a high of in July, although a record low of was recorded in February 1996 and a record high of was recorded in July 2006. Average monthly precipitation ranged from in January to in June.

Major highways

Interstate 74 Interstate 80 Interstate 88 Interstate 280 U.S. Highway 6 U.S. Highway 67 U.S. Highway 150 Illinois Route 2 (formerly) Illinois Route 5 Illinois Route 84 Illinois Route 92 Illinois Route 94 Illinois Route 110 Illinois Route 192

Transit Quad Cities MetroLINK List of intercity bus stops in Illinois

Adjacent counties Clinton County, Iowa (north) Whiteside County (northeast) Henry County (southeast) Mercer County (south) Louisa County, Iowa (southwest) Muscatine County, Iowa (west) Scott County, Iowa (northwest)

National protected area Upper Mississippi River National Wildlife and Fish Refuge (part)

Demographics

2020 census

As of the 2020 census, the county had a population of 144,672. The median age was 40.6 years. 22.1% of residents were under the age of 18 and 19.9% of residents were 65 years of age or older. For every 100 females there were 96.8 males, and for every 100 females age 18 and over there were 94.6 males age 18 and over.

The racial makeup of the county was 71.2% White, 11.5% Black or African American, 0.5% American Indian and Alaska Native, 2.8% Asian, <0.1% Native Hawaiian and Pacific Islander, 5.2% from some other race, and 8.8% from two or more races. Hispanic or Latino residents of any race comprised 13.7% of the population.

The 2020 census counted 88.5% of residents living in urban areas and 11.5% living in rural areas.

There were 60,735 households in the county, of which 27.4% had children under the age of 18 living in them. Of all households, 42.1% were married-couple households, 20.6% were households with a male householder and no spouse or partner present, and 30.0% were households with a female householder and no spouse or partner present. About 33.5% of all households were made up of individuals and 14.7% had someone living alone who was 65 years of age or older.

There were 66,729 housing units, of which 9.0% were vacant. Among occupied housing units, 66.4% were owner-occupied and 33.6% were renter-occupied. The homeowner vacancy rate was 2.1% and the rental vacancy rate was 10.7%.

Racial and ethnic composition +Rock Island County, Illinois – Racial and ethnic compositionRace / Ethnicity (NH = Non-Hispanic)Pop 1980Pop 1990Pop 2000Pop 2010 Pop 2020% 1980% 1990% 2000% 2010% 2020White alone (NH)147,393128,986121,705111,76497,68988.81%86.73%81.48%75.75%67.52%Black or African American alone (NH)9,71010,29011,09912,91116,1695.85%6.92%7.43%8.75%11.18%Native American or Alaska Native alone (NH)2573012882832400.15%0.20%0.19%0.19%0.17%Asian alone (NH)8899801,4992,3834,0330.54%0.66%1.00%1.62%2.79%Native Hawaiian or Pacific Islander alone (NH)x included in the Asian category in the 1980 Censusx included in the Asian category in the 1990 Census344435xx0.02%0.03%0.02%Other race alone (NH)510821091354820.31%0.06%0.07%0.09%0.33%Mixed race or Multiracial (NH)x not an option in the 1980 Censusx not an option in the 1990 Census1,8492,9086,182xx1.24%1.97%4.27%Hispanic or Latino (any race)7,2098,08412,79117,11819,8424.34%5.44%8.56%11.60%13.72%Total165,968148,723149,374147,546144,672 100.00%100.00%100.00%100.00%100.00%

Racial / Ethnic Profile of places in Rock Island County, Illinois (2020 census) Racial / Ethnic Profile of places in Rock Island County, Illinois (2020 Census)Following is a table of towns and census designated places in Rock Island County, Illinois. Data for the United States (with and without Puerto Rico), the state of Illinois, and Rock Island County itself have been included for comparison purposes. The majority racial/ethnic group is coded per the key below. Communities that extend into and adjacent county or counties are delineated with a followed by an accompanying explanatory note. The full population of each community has been tabulated including the population in adjacent counties. Majority minority with no dominant groupMajority WhiteMajority BlackMajority HispanicMajority Asian

+Racial and ethnic composition of places in Rock Island County, Illinois (2020 Census) (NH = Non-Hispanic)PlaceDesignationTotal PopulationWhite alone (NH)%Black or African American alone (NH)%Native American or Alaska Native alone (NH)%Asian alone (NH)%Pacific Islander alone (NH)%Other race alone (NH)%Mixed race or Multiracial (NH)%Hispanic or Latino (any race)%United States of America (50 states and D.C.) x331,449,281191,697,64757.84%39,940,33812.05%2,251,6990.68%19,618,7195.92%622,0180.19%1,689,8330.51%13,548,9834.09%62,080,04418.73% x334,735,155191,722,19557.28%39,944,62411.93%2,252,0110.67%19,621,4655.86%622,1090.19%1,692,3410.51%13,551,3234.05%65,329,08719.52% State 12,812,508 7,472,751 58.32% 1,775,612 13.86% 16,561 0.13% 747,280 5.83% 2,959 0.02% 45,080 0.35% 414,855 3.24% 2,337,410 18.24% County 144,672 97,689 67.52% 16,169 11.18% 240 0.17% 4,033 2.79% 35 0.02% 482 0.33% 6,182 4.27% 19,842 13.72% East Moline City 21,374 11,643 54.47% 3,776 17.67% 29 0.14% 787 3.68% 0 0.00% 60 0.28% 816 3.82% 4,263 19.94% Moline City 42,985 28,038 65.23% 3,661 8.52% 75 0.17% 1,276 2.97% 13 0.03% 132 0.31% 1,759 4.09% 8,031 18.68% Rock Island City 37,108 21,910 59.04% 7,135 19.23% 63 0.17% 1,603 4.32% 12 0.03% 160 0.43% 1,928 5.20% 4,297 11.58% Silvis City 8,003 5,366 67.05% 731 9.13% 20 0.25% 174 2.17% 1 0.01% 25 0.31% 332 4.15% 1,354 16.92% Andalusia Village 1,184 1,099 92.82% 11 0.93% 5 0.42% 1 0.08% 0 0.00% 2 0.17% 30 2.53% 36 3.04% Carbon Cliff Village 1,846 1,204 65.22% 299 16.20% 6 0.33% 11 0.60% 2 0.11% 7 0.38% 92 4.98% 225 12.19% Coal Valley partly in Henry county Village 3,873 3,411 88.07% 35 0.90% 4 0.10% 30 0.77% 2 0.05% 8 0.21% 137 3.54% 246 6.35% Cordova Village 671 622 92.70% 4 0.60% 2 0.30% 0 0.00% 0 0.00% 5 0.75% 16 2.38% 22 3.28% Hampton Village 1,779 1,511 84.94% 25 1.41% 2 0.11% 5 0.28% 0 0.00% 13 0.73% 77 4.33% 146 8.21% Hillsdale Village 417 384 92.09% 1 0.24% 1 0.24% 0 0.00% 0 0.00% 2 0.48% 16 3.84% 13 3.12% Milan Village 5,097 4,130 81.03% 289 5.67% 13 0.26% 55 1.08% 2 0.04% 20 0.39% 273 5.36% 315 6.18% Oak Grove Village 476 414 86.97% 0 0.00% 0 0.00% 5 1.05% 1 0.21% 0 0.00% 22 4.62% 34 7.14% Port Byron Village 1,668 1,506 90.29% 10 0.60% 2 0.12% 7 0.42% 0 0.00% 10 0.60% 48 2.88% 85 5.10% Rapids City Village 964 889 92.22% 8 0.83% 1 0.10% 1 0.10% 0 0.00% 1 0.10% 27 2.80% 37 3.84% Reynolds partly in Mercer county Village 498 467 93.78% 2 0.40% 0 0.00% 0 0.00% 0 0.00% 1 0.20% 20 4.02% 8 1.61% Barstow CDP 89 83 93.26% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 1 1.12% 1 1.12% 4 4.49% Buffalo Prairie CDP 64 57 89.06% 0 0.00% 0 0.00% 1 1.56% 0 0.00% 0 0.00% 5 7.81% 1 1.56% Campbell's Island CDP 275 247 89.82% 1 0.36% 1 0.36% 0 0.00% 0 0.00% 0 0.00% 8 2.91% 18 6.55% Coyne Center CDP 877 784 89.40% 13 1.48% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 53 6.04% 27 3.08% Edgington CDP 391 374 95.65% 1 0.26% 2 0.51% 0 0.00% 0 0.00% 0 0.00% 2 0.51% 12 3.07% Illinois City CDP 159 144 90.57% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 5 3.14% 10 6.29% Joslin CDP 85 81 95.29% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 0 0.00% 3 3.53% 1 1.18% Rock Island Arsenal CDP 182 101 55.49% 24 13.19% 0 0.00% 9 4.95% 0 0.00% 6 3.30% 26 14.29% 16 8.79% Taylor Ridge CDP 141 127 90.07% 0 0.00% 1 0.71% 0 0.00% 0 0.00% 0 0.00% 8 5.67% 5 3.55%

2010 census As of the 2010 United States census, there were 147,546 people, 61,303 households, and 38,384 families residing in the county. The population density was . There were 65,756 housing units at an average density of . The racial makeup of the county was 81.6% white, 9.0% black or African American, 1.6% Asian, 0.3% American Indian, 4.4% from other races, and 3.0% from two or more races. Those of Hispanic or Latino origin made up 11.6% of the population. In terms of ancestry, 25.9% were German, 14.2% were Irish, 8.7% were English, 6.8% were Swedish, and 5.2% were American.

Of the 61,303 households, 29.0% had children under the age of 18 living with them, 45.3% were married couples living together, 12.7% had a female householder with no husband present, 37.4% were non-families, and 31.6% of all households were made up of individuals. The average household size was 2.34 and the average family size was 2.93. The median age was 40.0 years.

The median income for a household in the county was $46,226 and the median income for a family was $58,962. Males had a median income of $42,548 versus $31,917 for females. The per capita income for the county was $25,071. About 8.7% of families and 12.3% of the population were below the poverty line, including 19.0% of those under age 18 and 7.1% of those age 65 or over.

Economy At one time Mississippi Valley Airlines had its headquarters in Quad City Airport in the county."World Airline Directory." Flight International. March 30, 1985. 98 . "Head Office: PO Box 949, Quad City Airport, Moline, Illinois 61265, USA." John Deere is headquartered in Moline.

Communities

Cities East Moline Moline Rock Island Silvis

Villages

Andalusia Carbon Cliff Coal Valley (part) Cordova Hampton Hillsdale Milan Oak Grove Port Byron Rapids City Reynolds (part)

Census-designated places Barstow Buffalo Prairie Campbell's Island Coyne Center Edgington Illinois City Joslin Rock Island Arsenal Taylor Ridge

Townships Rock Island County is divided into eighteen townships:

Andalusia Blackhawk Bowling Buffalo Prairie Canoe Creek Coal Valley Coe Cordova Drury Edgington Hampton Moline Port Byron Rock Island Rural South Moline South Rock Island Zuma

Forts

Fort Armstrong

Politics Before 1932, Rock Island County was a Republican stronghold in presidential elections, backing the party's candidate in every election from 1892 to 1928. From 1932 on, it has consistently backed Democratic Party presidential candidates, except for the national Republican landslides of 1952, 1956, 1972, and 1980. In 2016, Donald Trump managed to keep Hillary Clinton to a single-digit margin of victory, the first Republican to do so since Ronald Reagan in 1984; in 2020, Joe Biden increased the Democratic margin from 8.3% to 12.1%. Due to the dominance of the Democratic Party in county politics, Rock Island County remains one of the most Democratic counties outside of the Chicago area in Illinois. Since 2010 the Republican Party began making inroads in county politics, gaining a few seats on the Democratic-dominated county board; however, since 2018, the Republican Party influence on the board has begun to decrease as the county resumed heavy Democratic voting.

Education K-12 school districts include: - Text list

Erie Community Unit School District 1 Mercer County School District 404