Dubuque County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 99,266, making it the eighth-most populous county in Iowa. The county seat is Dubuque. The county is named for Julien Dubuque, the first European settler of Iowa.

Dubuque County comprises the Dubuque, IA Metropolitan Statistical Area.

Dubuque County is named for French trader Julien Dubuque, the first European settler of Iowa, and an early lead mining pioneer in what is now Dubuque County. Dubuque was French Canadian, and had (by most accounts) a friendly relationship with the local Meskwaki people. He and other early pioneers established a lucrative mining and trading industry in the area. When lead deposits began becoming exhausted, the pioneers developed boat building, lumber yards, milling, brewing, and machinery manufacturing to take its place.

The city of Dubuque was chartered in 1833 as the first city in Iowa. The establishment of the City of Dubuque in 1833 led to large-scale settlement of the surrounding area. This was greatly encouraged by the Roman Catholic Church, which sent priests, bishops, and nuns to establish churches in the unpopulated countryside. Primarily, Irish and German (many of whom were Catholic) immigrants came to the region.

At an extra session of the Sixth Legislative Assembly of Michigan Territory held in September 1834, the Iowa District was divided into two counties by running a line due west from the lower end of Rock Island in the Mississippi River. The territory north of this line (which started just south of the present-day Davenport) was named Dubuque County, and all south of it was Demoine County [sic]. Thus, at that time Dubuque County nominally included not only much of what is now the state of Minnesota but portions of what are now North Dakota and South Dakota.

Dubuque County became part of Wisconsin Territory once it was split off from Michigan Territory on July 3, 1836. A massive reorganization and reduction of the county's size was executed on December 21, 1837, when its original area was separated into 13 named new counties and a "non-county area". The land in present day Minnesota and the Dakotas was transferred to the newly created Fayette County in this action. Dubuque County became a part of Iowa Territory upon its creation on July 4, 1838.

In 1858, Saint Francis Catholic Church was established in Dubuque County.

In the 1980s, the farm crisis set in, and devastated large sections of the Midwest, including Dubuque County. Since the area was heavily dependent on agriculture-related industries like Deere and Company and the Dubuque Packing Company, unemployment soared. In one month of 1982, Dubuque County had 23% unemployment, the highest in the nation. The county experienced huge population losses during this time, as workers left the area. It would not fully recover from this until the late 1990s, when the economy diversified, shifting away from manufacturing, and toward various service-related establishments. The county is now growing and flourishing.

This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (July 2020) (Learn how and when to remove this message)

Since the 1990s, the area has become much more prosperous. Today, the county boasts record employment levels and a growing population. The surging economy can especially be seen in the West Side of the City of Dubuque, and in neighboring Peosta and Asbury. These areas have expanded so much that concerns now lie with trying to manage the growth, a sharp change from just 20 years ago.

It is one of Iowa's two original counties along with Des Moines County; both were organized by the Michigan Territorial legislature in 1834.

In 2021, the Dubuque County Minutemen baseball team advanced to the American Legion World Series semi-finals, the first team from Iowa to advance that far since Cedar Rapids, IA in 1975.

Dubuque County is governed by a three-member Board of Supervisors elected at large. Current supervisors include Ann McDonough, Wayne Kenniker and Harley Pothoff (chairperson). They meet the 1st and 3rd Monday of each month at 9:00 a.m. in the Dubuque County Courthouse.

The current county attorney is Scott Nelson, who succeeded C.J. May in 2023.

The current county auditor is Kevin Dragotto, who succeeded Denise Dolan in 2021.

The current county treasurer is Michael Clasen, who succeeded Eric Steirman in 2022

Dubuque County Sheriff's Office
Abbreviation	DCSO
Jurisdictional structure
Operations jurisdiction	Dubuque, Iowa, USA
Map of Dubuque County Sheriff's Office's jurisdiction
Size	617 square miles (1,600 km)
Population	92,359 (2006)
General nature	Local civilian police
Operational structure
Headquarters	770 Iowa Street, Dubuque, Iowa
Sheriff responsible	Joseph L. Kennedy (since 2016)
Website
Official website

The county sheriff's office provides law enforcement services for unincorporated areas of Dubuque County, as well as providing courthouse security, operating the county jail, and performing civil procedures. The Sheriff's Department is located at the Dubuque City/County Law Enforcement Center. The department shares facilities and other resources with the Dubuque Police Department.

The county borders on Illinois and Wisconsin, and is bounded on the northeast by the Mississippi River. According to the U.S. Census Bureau, the county has a total area of 617 square miles (1,600 km), of which 608 square miles (1,570 km) is land and 8.3 square miles (21 km) (1.4%) is water. The county is drained by north and south forks of the Maquoketa River.

The county seat is Dubuque, Iowa, which is located along the Mississippi River in the east-central portion of the county. Eastern Dubuque County is markedly different from the western portion in that its topography is very uneven. The city of Dubuque and surrounding areas adjacent to the Mississippi River have many steep hills, bluffs, and ravines. Also, the eastern portion is more heavily wooded than the west, which is mostly rolling farmland.

Dubuque County is widely known for its impressive bluffs along the Mississippi River, which run along the entire length of the county's riverbanks. These form part of Iowa's Coulee Region, otherwise known as the Driftless Area. During the last ice age, much of the Mississippi Valley near Dubuque County was bypassed by glacial flows, which flattened the surrounding land in eastern Illinois, Wisconsin, and western Iowa, leaving the Driftless Area unusually rugged.

The Iowa Department of Natural Resources administers 3 park and preserve areas in the county:

• Little Maquoketa River Mounds State Preserve
• Mines of Spain State Recreation Area/E. B. Lyons Nature Center
• White Pine Hollow State Forest

The Dubuque County Conservation Board administers 11 park and recreation areas in the county:

The City of Dubuque and other towns in the county also operate public park systems of their own. (see Parks in Dubuque, Iowa)

• The Jule

• Clayton County (north)
• Grant County, Wisconsin (northeast)
• Jo Daviess County, Illinois (east)
• Jackson County (southeast)
• Jones County (southwest)
• Delaware County (west)

• Driftless Area National Wildlife Refuge (part)
• Upper Mississippi River National Wildlife and Fish Refuge (part)

Historical population

Census	Pop.	Note	%±
1840	3,059		—
1850	10,841		254.4%
1860	31,164		187.5%
1870	38,969		25.0%
1880	42,996		10.3%
1890	49,848		15.9%
1900	56,403		13.1%
1910	57,450		1.9%
1920	58,262		1.4%
1930	61,214		5.1%
1940	63,768		4.2%
1950	71,337		11.9%
1960	80,048		12.2%
1970	90,609		13.2%
1980	93,745		3.5%
1990	86,403		−7.8%
2000	89,143		3.2%
2010	93,653		5.1%
2020	99,266		6.0%
2023 (est.)	98,887		−0.4%
U.S. Decennial Census 1790-1960 1900-1990 1990-2000 2010-2019

The 2020 census recorded a population of 99,266 in the county, with a population density of 160.6862/sq mi (62.04130/km). There were 42,630 housing units of which 39,891 were occupied.

Dubuque County Racial Composition

Race	Num.	Perc.
White (NH)	87,349	88%
Black or African American (NH)	4,035	4.1%
Native American (NH)	131	0.13%
Asian (NH)	1,018	1.02%
Pacific Islander (NH)	813	0.82%
Other/Mixed (NH)	2,943	3%
Hispanic or Latino	2,977	3%

The 2010 census recorded a population of 93,653 in the county, with a population density of 153.9940/sq mi (59.4574/km). There were 38,951 housing units, of which 36,815 were occupied.

At the 2000 census, there were 89,143 people, 33,690 households and 23,111 families residing in the county. The population density was 147 per square mile (57/km). There were 35,505 housing units at an average density of 58 per square mile (22/km). The racial makeup of the county was 97.07% White, 0.86% Black or African American, 0.15% Native American, 0.58% Asian, 0.09% Pacific Islander, 0.50% from other races, and 0.76% from two or more races. 1.19% of the population were Hispanic or Latino of any race.

2005 estimates by the census indicated that Dubuque had a population that identified itself as being 95.5% non-Hispanic white, 1.3% African American, 0.7% Asian and 1.5% Latino.

There were 33,690 households, of which 33.10% had children under the age of 18 living with them, 56.80% were married couples living together, 8.70% had a female householder with no husband present, and 31.40% were non-families. 26.70% of all households were made up of individuals, and 10.80% had someone living alone who was 65 years of age or older. The average household size was 2.51 and the average family size was 3.07.

25.60% of the population were under the age of 18, 10.20% from 18 to 24, 27.20% from 25 to 44, 22.30% from 45 to 64, and 14.70% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 94.40 males. For every 100 females age 18 and over, there were 91.30 males.

The median household income was $39,582 and the median family income was $48,742. Males had a median income of $31,977 versus $22,309 for females. The per capita income for the county was $19,600. About 4.90% of families and 7.80% of the population were below the poverty line, including 7.80% of those under age 18 and 11.00% of those age 65 or over.

This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources in this section. Unsourced material may be challenged and removed. Find sources: "Dubuque County, Iowa" – news · newspapers · books · scholar · JSTOR (January 2023) (Learn how and when to remove this message)

Historically, Dubuque County's economy was driven by heavy industry, including, among others, Deere and Company, and the now-defunct Dubuque Packing Company. However, within the last 20 years, and especially within the last 10 years, the economy has diversified a great deal. Now, alongside manufacturing, which still employs thousands of workers, many county residents work in the tourism/gaming, health care, education, publishing, and financial service sectors.

The county's economy is largely centered around business and industry within the City of Dubuque. With the exception of industrial areas in Cascade, Dyersville, and Peosta, almost all of the rest of the county is rural and agriculturally driven. Some of the key industries in Dubuque County include: Deere and Company, Eagle Window & Door Co., Flexsteel Industries, Mi-T-M Corp., A.Y. McDonald Mfg. Co., Klauer Mfg., Georgia-Pacific, and Swiss Valley Farms, among others. Besides industry, large numbers of people work for the Dubuque Community School District, Mercy Medical Center - Dubuque, Medical Associates, Finley Hospital, Prudential Financial, the City of Dubuque, and Cottingham & Butler.

Dubuque County has, in recent years, enjoyed job growth, low unemployment, and the rapid expansion of business and commerce. Alongside these positives, the county is beginning to see a growing population, as well. Up from a recent low of 86,403 in 1990, the population is now about 97,000 and growing. This can be seen especially in the West Side of the City of Dubuque, and in nearby Asbury and Peosta. This fact is especially significant, considering that all of the counties surrounding Dubuque County have fewer people now than they did in 1900, with the exception of Grant County, Wisconsin.

United States presidential election results for Dubuque County, Iowa

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	28,224	53.48%	23,705	44.92%	841	1.59%
2020	27,214	50.47%	25,657	47.58%	1,055	1.96%
2016	23,460	47.18%	22,850	45.96%	3,411	6.86%
2012	21,280	41.81%	28,768	56.53%	846	1.66%
2008	18,651	38.89%	28,611	59.65%	701	1.46%
2004	20,100	42.73%	26,561	56.46%	382	0.81%
2000	16,462	40.83%	22,341	55.41%	1,520	3.77%
1996	13,391	35.19%	20,839	54.77%	3,821	10.04%
1992	14,007	32.60%	20,539	47.80%	8,422	19.60%
1988	14,530	37.69%	23,797	61.74%	220	0.57%
1984	19,239	46.37%	21,876	52.72%	376	0.91%
1980	18,649	44.90%	18,689	44.99%	4,201	10.11%
1976	17,459	44.71%	20,548	52.62%	1,042	2.67%
1972	17,272	47.29%	18,417	50.43%	832	2.28%
1968	14,197	40.72%	18,664	53.54%	2,002	5.74%
1964	10,104	29.87%	23,695	70.06%	24	0.07%
1960	12,740	36.64%	22,007	63.30%	19	0.05%
1956	17,923	57.36%	13,174	42.16%	150	0.48%
1952	18,075	55.03%	14,542	44.27%	228	0.69%
1948	10,111	39.02%	15,521	59.90%	281	1.08%
1944	12,502	49.11%	12,867	50.54%	89	0.35%
1940	14,590	51.30%	13,805	48.54%	46	0.16%
1936	8,275	30.22%	16,291	59.50%	2,812	10.27%
1932	6,747	24.99%	19,210	71.15%	1,042	3.86%
1928	9,744	33.30%	19,437	66.42%	81	0.28%
1924	8,280	32.77%	5,718	22.63%	11,269	44.60%
1920	12,436	59.22%	7,636	36.36%	928	4.42%
1916	5,772	47.22%	6,063	49.60%	388	3.17%
1912	1,620	13.82%	6,237	53.20%	3,867	32.98%
1908	4,708	39.71%	6,645	56.05%	502	4.23%
1904	5,485	48.31%	4,913	43.27%	955	8.41%
1900	4,752	41.09%	6,655	57.55%	157	1.36%
1896	5,203	43.73%	6,510	54.72%	185	1.55%

Dubuque County was historically Democratic and supported every Democratic Party Presidential candidate from John F. Kennedy to Barack Obama, with President Obama winning the county by over 20 points in 2008. In 2016, it was narrowly won by Donald Trump, who became the first Republican to win the county since President Eisenhower in 1956. Trump won the county again in 2020, by a larger margin. In the 2022 elections, the county continued to trend rightward, with Republican governor Kim Reynolds winning reelection by a margin of over 16 points. The county additionally voted for Republican Chuck Grassley in U.S. Senate election and for Republican Ashley Hinson in the election for U.S. House of Representatives for Iowa's 1st congressional district.

Tertiary education:

K-12 school districts include:

• Dubuque Community School District
• Maquoketa Community School District
• Monticello Community School District
• Western Dubuque Community School District

As of 2022, Dubuque County has a large percentage of Catholic residents.

• Fillmore
• Key West
• Washington Mills

Dubuque County is divided into eighteen townships:

List of Cities in Dubuque County ranked by population
Recorded by the United States Census Bureau

† 'county seat'

Rank	City	2020 City Population	2010 City Population	Change
1	Dubuque†	59,667	57,637	+3.52%
2	Asbury	5,943	4,170	+42.52%
3	Dyersville (partially in Delaware County)	4,477	4,058	+10.33%
4	Cascade (partially in Jones County)	2,386	2,159	+10.51%
5	Epworth	2,023	1,860	+8.76%
6	Peosta	1,908	1,377	+38.56%
7	Farley	1,766	1,537	+14.90%
8	New Vienna	382	407	−6.14%
9	Worthington	382	401	−4.74%
10	Holy Cross	356	374	−4.81%
11	Luxemburg	245	240	+2.08%
12	Rickardsville	202	182	+10.99%
13	Sherrill	189	177	+6.78%
14	Centralia	116	134	−13.43%
15	Bernard	114	112	+1.79%
16	Sageville	95	122	−22.13%
17	Zwingle (partially in Jackson County)	84	91	−7.69%
18	Balltown	79	68	+16.18%
19	Bankston	23	25	−8.00%
20	Durango	20	22	−9.09%

• List of counties in Iowa
• National Register of Historic Places listings in Dubuque County, Iowa

• Dubuque County Government website