About 10,000 years ago almost 90% of Koochiching County was covered byLake Agassiz. When it receded it left low areas of decayedvegetation (muskeg); as a result, three-quarters of northern Koochiching are underlain with 2 to 50 feet ofpeat.[4]
The name "Koochiching" comes from either theOjibwe wordGojijiingcode: oji promoted to code: oj orCreeKocicīhkcode: cre promoted to code: cr (recorded in some documents as "Ouchichiq"), both meaning 'at the place of inlets', referring to the neighboringRainy Lake andRiver. ReverendJ.A. Gilfillan recorded their meaning, "according to some, Neighbor lake, according to others a lake somewhere", possibly referring to the neighboringRainy Lake and toLake Couchiching located in southernOntario. Early French inhabitants gave the namesLac à la Pluie ('Rainy Lake') andRivière à la Pluie ('Rainy River') to the nearby bodies of water because of the mist-like rain present at the falls ofRainy River and then to the settlement that became known asInternational Falls.
This area was among the last in Minnesota to be settled. European settlers in Koochiching County started coming in the late 1800s. Some of the last lands were ceded from the Chippewa in a 1904 Land Act.[5] Homesteads were being proven primarily in the 1900-1910 decade.[6] Settlers were lumberjacks and farmers and many other trades, they "suffered through isolation, illness, harsh weather, and poverty... They built schools, churches, and fought for good roads".[7]
The county is one of the youngest in the state, having been created in 1906 after separating fromItasca County.
Koochiching County lies on the northern edge of Minnesota. Its northern border abuts the south border ofCanada (across theRainy River). The Rainy River flows west-northwestward along its north border, being fed by several rivers which drain from the county into the Rainy:Rat Root River drains the east central part of the county; Little Fork River flows northward through the eastern part of the county; Big Fork River flows northward through the east-central part of the county; Black River flows northward through the central part of the county; Rapid River and East Fork Rapid River flow north-northwestward through the western part of the county, joining in the northwestern part of the county shortly before exiting the county's west line to discharge into the Rainy, just west of the county's northwestern corner.
The county terrain consists of low rolling hills, with swampy areas whereLake Agassiz basin was deepest. There are also deposits ofpeat from 1½ to 50 feet in the low areas. The fairly level soil is broken by ledges ofPrecambrian rock.Bedrock in the area includes Elygreenstone and greenstone schists that are said to be among the oldest on the planet.[8] The terrain slopes to the north, with its highest point on the western part of its southern border at 1,515 ft (462 m) ASL.[9] The county has a total area of 3,154 square miles (8,170 km2), of which 3,104 square miles (8,040 km2) is land and 50 square miles (130 km2) (1.6%) is water.[10] It is the second-largest county in Minnesota by land area (second to neighboringSt. Louis County) and third-largest by total area.
As of thecensus of 2000, there were 14,355 people, 6,040 households, and 3,962 families in the county. Thepopulation density was 4.62 per square mile (1.78/km2). There were 7,719 housing units at an average density of 2.49 per square mile (0.96/km2). The racial makeup of the county was 96.12%White, 0.19%Black orAfrican American, 2.15%Native American, 0.17%Asian, 0.06%Pacific Islander, 0.08% fromother races, and 1.23% from two or more races. 0.56% of the population wereHispanic orLatino of any race. 21.2% were ofNorwegian, 19.8%German, 12.3%Swedish and 7.0%Irish ancestry.
There were 6,040 households, out of which 28.40% had children under the age of 18 living with them, 53.30% weremarried couples living together, 8.50% had a female householder with no husband present, and 34.40% were non-families. 30.40% of all households were made up of individuals, and 14.50% had someone living alone who was 65 years of age or older. The average household size was 2.33 and the average family size was 2.88.
The county population contained 23.90% under the age of 18, 6.40% from 18 to 24, 25.80% from 25 to 44, 26.00% from 45 to 64, and 18.00% who were 65 years of age or older. The median age was 42 years. For every 100 females there were 98.50 males. For every 100 females age 18 and over, there were 95.20 males.
The median income for a household in the county was $36,262, and the median income for a family was $43,608. Males had a median income of $40,642 versus $22,261 for females. Theper capita income for the county was $19,167. About 8.40% of families and 12.10% of the population were below thepoverty line, including 16.10% of those under age 18 and 13.40% of those age 65 or over.
From1932 through1996, Koochiching County voters tended Democratic, selecting the Democratic nominee in every election saveNixon's1972 landslide. In2000,George W. Bush became the first Republican to carry the county since 1972, despite narrowly losing the overall national popular vote. It returned to the Democratic column in the subsequent three elections, although none of the Democratic nominees in those three elections managed as high a vote share asMondale in1984 orDukakis in1988. In2016,Donald Trump became the second Republican since 1972 to carry the county, and carried it again in2020, with an increased majority—the first time the county has ever voted Republican two elections in a row. Trump won Koochiching County for a third time in2024, taking nearly 62% of the vote, becoming the first ever Republican to win more than 60% of the county's vote.[17]
United States presidential election results for Koochiching County, Minnesota[18][19]
Koochiching County is one of two counties in Minnesota that have no organizedcivil township governments within the county (the other is neighboring Lake of the Woods County), due to legislative action taken by the county to absorb existing township governments.Survey townships, as defined by thePublic Land Survey System exist but are not organized. Six city governments have been created, and the rest of the county consists of unorganized territories and unincorporated communities.
Koochiching County is the location of the fictional town ofFrostbite Falls, the home of the animated charactersRocky and Bullwinkle. Frostbite Falls was probably named in honor of International Falls, since International Falls is often referred to as the nation's icebox.[28]