Aitkin County (/ˈeɪkɪn/ AY-kin) is a county in the U.S. state of Minnesota. As of the 2020 census, the population was 15,697. Its county seat is Aitkin. Part of the Mille Lacs Indian Reservation is in the county. The county was created in 1857 and organized in 1871.

Aitkin County was established in 1857 as Aiken County. The current spelling was adopted in 1872. It was named for William Alexander Aitken, a fur trader for the American Fur Company, under John Jacob Astor. Formed from Ramsey and Pine counties, Aiken County originally consisted of the 17 townships closest to Mille Lacs Lake. It acquired outlands of Ramsey, Itasca and Pine Counties to its north and east. It was organized in 1871, taking up lands from Cass and Itasca Counties and losing a point in the southwestern corner to Crow Wing County to form its current boundaries.

The Mississippi River flows southward through the west central part of the county. The county terrain consists of wooded rolling hills, dotted with lakes and ponds. The terrain slopes to the south; its highest point is Quadna Mountain, 2.5 miles (4.0 km) south-southeast of Hill City, at 1,591 ft (485 m) ASL. Otherwise the highest terrain is near its northwestern corner, at 1,388 ft (423 m) ASL. The county has a total area of 1,995 square miles (5,170 km), of which 1,822 square miles (4,720 km) is land and 174 square miles (450 km) (8.7%) is water.

Aitkin, Minnesota
Climate chart (explanation)
J F M A M J J A S O N D     1     20 0     0.8     26 4     1.7     38 16     2.6     54 30     3.1     66 40     4.5     75 51     4.2     80 56     3.2     77 53     3.3     68 45     2.9     55 34     1.6     38 21     1     24 7 █ Average max. and min. temperatures in °F █ Precipitation totals in inches Source: The Weather Channel
Metric conversion J F M A M J J A S O N D     25     −7 −18     20     −3 −16     43     3 −9     66     12 −1     79     19 4     113     24 11     105     27 13     81     25 12     84     20 7     73     13 1     40     3 −6     26     −4 −14 █ Average max. and min. temperatures in °C █ Precipitation totals in mm

In recent years, average temperatures in the county seat of Aitkin have ranged from a low of 0 °F (−18 °C) in January to a high of 80 °F (27 °C) in July, although a record low of −47 °F (−44 °C) was recorded in January 1972 and a record high of 100 °F (38 °C) was recorded in August 1976. Although these records are the official records, temperatures above 100 °F (38 °C) has been detected numerous times throughout Aitkin County and surrounding areas. Average monthly precipitation ranged from 0.79 inches (20 mm) in February to 4.46 inches (113 mm) in June.

Historical population

Census	Pop.	Note	%±
1860	2		—
1870	178		8,800.0%
1880	366		105.6%
1890	2,462		572.7%
1900	6,473		162.9%
1910	10,371		60.2%
1920	15,043		45.0%
1930	15,009		−0.2%
1940	17,865		19.0%
1950	14,327		−19.8%
1960	12,162		−15.1%
1970	11,403		−6.2%
1980	13,404		17.5%
1990	12,425		−7.3%
2000	15,301		23.1%
2010	16,202		5.9%
2020	15,697		−3.1%
2023 (est.)	16,102		2.6%
U.S. Decennial Census 1790-1960 1900-1990 1990-2000 2010-2020

Aitkin County Racial Composition

Race	Num.	Perc.
White (NH)	14,479	92.24%
Black or African American (NH)	58	0.37%
Native American (NH)	376	2.4%
Asian (NH)	38	0.24%
Pacific Islander (NH)	1	0.01%
Other/Mixed (NH)	525	3.34%
Hispanic or Latino	220	1.4%

As of the census of 2010, there were 16,202 people, 7,542 households, and 4,458 families in the county. The population density was 8.89 per square mile (3.43/km). There were 16,626 housing units at an average density of 9.13 per square mile (3.53/km). The racial makeup of the county was 95.63% or 15,494 people White, 0.35% or 57 people Black or African American, 2.4% or 390 people Native American, 0.17% or 27 people Asian, 0.025% or 4 people Pacific Islander, 0.13% or 21 people from other races, and 1.29% or 209 people from two or more races. Of the population with two or more races, 0.9% of the population were Hispanic or Latino of any race. 29.5% were of German, 14.3% Norwegian, 13.0% Swedish, 6.2% Irish, 5.3% United States or American and 5.2% Finnish ancestry.

There were 6,644 households, out of which 22.60% had children under the age of 18 living with them, 57.50% were married couples living together, 6.30% had a female householder with no husband present, and 32.90% were non-families. 28.70% of all households were made up of individuals, and 14.00% had someone living alone who was 65 years of age or older. The average household size was 2.28 and the average family size was 2.76.

The county population contained 20.90% under the age of 18, 5.50% from 18 to 24, 21.60% from 25 to 44, 29.10% from 45 to 64, and 23.00% who were 65 years of age or older. The median age was 46 years. For every 100 females there were 101.60 males. For every 100 females age 18 and over, there were 99.90 males.

The median income for a household in the county was $44,139, and the median income for a family was $58,290. Males had a median income of $51,604 versus $30,633 for females. The per capita income for the county was $21,848. About 5.20% of families and 7.60% of the population were below the poverty line, including 15.50% of those under age 18 and 11.00% of those age 65 or over.

Aitkin County voters have selected the Democratic Party candidate in 62.5% of national elections since 1960, as of 2020. Recent presidential elections have shifted to the Republican Party, with their candidate winning five of the last six elections as of 2024 and their lone loss in that span coming by just 6 votes.

United States presidential election results for Aitkin County, Minnesota

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	6,741	64.53%	3,524	33.74%	181	1.73%
2020	6,258	62.42%	3,607	35.98%	160	1.60%
2016	5,516	59.76%	3,134	33.95%	581	6.29%
2012	4,533	49.58%	4,412	48.26%	197	2.15%
2008	4,589	48.77%	4,595	48.83%	226	2.40%
2004	4,768	50.44%	4,539	48.02%	145	1.53%
2000	3,755	45.46%	3,830	46.37%	675	8.17%
1996	2,327	31.43%	3,810	51.46%	1,267	17.11%
1992	2,151	28.46%	3,400	44.98%	2,008	26.56%
1988	3,011	43.37%	3,863	55.65%	68	0.98%
1984	3,422	46.14%	3,943	53.17%	51	0.69%
1980	3,396	44.28%	3,677	47.94%	597	7.78%
1976	2,476	35.63%	4,308	61.99%	165	2.37%
1972	3,241	53.73%	2,687	44.55%	104	1.72%
1968	2,254	39.84%	3,094	54.69%	309	5.46%
1964	2,000	33.96%	3,874	65.77%	16	0.27%
1960	3,097	50.66%	2,980	48.75%	36	0.59%
1956	2,762	50.18%	2,733	49.65%	9	0.16%
1952	3,384	55.93%	2,577	42.60%	89	1.47%
1948	2,466	41.05%	3,277	54.55%	264	4.39%
1944	2,720	49.37%	2,743	49.79%	46	0.83%
1940	3,744	50.12%	3,610	48.33%	116	1.55%
1936	2,466	37.30%	3,806	57.57%	339	5.13%
1932	2,341	40.76%	2,945	51.28%	457	7.96%
1928	3,951	70.10%	1,428	25.34%	257	4.56%
1924	2,720	53.67%	212	4.18%	2,136	42.15%
1920	2,933	70.15%	613	14.66%	635	15.19%
1916	1,122	46.23%	877	36.14%	428	17.63%
1912	362	17.38%	413	19.83%	1,308	62.79%
1908	1,205	67.02%	389	21.64%	204	11.35%
1904	1,327	80.96%	191	11.65%	121	7.38%
1900	988	77.31%	262	20.50%	28	2.19%
1896	855	69.46%	344	27.94%	32	2.60%
1892	445	62.59%	217	30.52%	49	6.89%

County Board of Commissioners

Position		Name	District
	Commissioner and Chairperson	J. Mark Wedel	District 1
	Commissioner	Laurie Westerlund	District 2
	Commissioner and Vice Chair	Travis Leiviska	District 3
	Commissioner	Bret Sample	District 4
	Commissioner	Michael Kearney	District 5

State Legislature (2018-2020)

Position		Name	Affiliation	District
	Senate	Carrie Ruud	Republican	District 10
	House of Representatives	Dale Lueck	Republican	District 10B

U.S. Congress (2018-2020)

Position		Name	Affiliation	District
	House of Representatives	Pete Stauber	Republican	8th
	Senate	Amy Klobuchar	Democrat	N/A
	Senate	Tina Smith	Democrat	N/A

• National Register of Historic Places listings in Aitkin County, Minnesota

• Aitkin County government’s website
• Minnesota Department of Transportation map of Aitkin County (southern portion, northern portion)
• Records

46°37′N 93°25′W / 46.61°N 93.41°W / 46.61; -93.41