The Wisconsin Territory was established by the federal government effective July 3, 1836, and existed until its eastern portion was granted statehood (as Wisconsin) in 1848. Therefore, the federal government set up the Minnesota Territory effective March 3, 1849. The newly organized territorial legislature created nine counties across the territory in October of that year. One of those original counties, Wabasha, had portions partitioned off in 1853 to create Fillmore and Rice counties. Then on February 20, 1855,[3] portions of Rice, Wabasha, and Fillmore counties were partitioned off to create the present county, with Rochester (which was also platted that year) as county seat. The county name recognized David Olmsted (1822-1861),[4] a member of the first territorial council and the fourth mayor of St. Paul.[5][6]
The county boundaries have remained unchanged since 1855.
Geography
Olmsted County is a fairly unusual mix of urban and rural areas in that there's no transition or buffer between the two environments. Rochester, Minnesota's third-largest city with roughly 118,000 people, sits in the Zumbro River valley at the center of the county. Outside the valley, with the exception of a small amount of urban growth in the last few years, is farmland with small agricultural communities and no directly adjacent suburbs. Stewartville, the county's second-largest city, has about 6,000 people.
Olmsted County is drained by three rivers, all flowing to the Mississippi. The Zumbro flows northward through the west central part of the county, into Wabasha County. The Whitewater flows northeast from the northeast part of the county into Winona County, and the Root flows east-southeastward through the lower part of the county into Fillmore County. The county terrain consists of low rolling hills, etched by drainage gullies and marked by occasional buttes. The available area is devoted to agriculture or developed for other uses.[7] The terrain slopes to the east and north,[8] and its highest point is a hill 7.5 miles (12.1 km) west of Stewartville, at 1,380 ft (420 m) ASL.[9] The county has an area of 655 square miles (1,700 km2), of which 653 square miles (1,690 km2) is land and 1.5 square miles (3.9 km2) (0.2%) is water.[10]
U.S. Decennial Census[13] 1790-1960[14] 1900-1990[15] 1990-2000[16] 2010-2020[1]
2020 census
As of the census of 2020,[17] the population was 162,847. The population density was 249.2 inhabitants per square mile (96.2/km2). There were 69,270 housing units at an average density of 106.0 per square mile (40.9/km2). The racial makeup of the county was 77.8% White, 6.8% Black or African American, 6.3% Asian, 0.4% Native American, 0.1% Pacific Islander, 2.5% from other races, and 6.1% from two or more races. Ethnically, the population was 5.6% Hispanic or Latino of any race.
As of the 2000 United States census, there were 124,277 people, 47,807 households, and 32,317 families in the county. The population density was 190 per square mile (73/km2). There were 49,422 housing units at an average density of 75.7 per square mile (29.2/km2). The racial makeup of the county was 90.33% White, 2.68% Black or African American, 0.26% Native American, 4.27% Asian, 0.03% Pacific Islander, 0.92% from other races, and 1.51% from two or more races. 2.38% of the population were Hispanic or Latino of any race.
There were 47,807 households, out of which 35.20% had children under the age of 18 living with them, 56.70% were married couples living together, 8.00% had a female householder with no husband present, and 32.40% were non-families. 25.80% of all households were made up of individuals, and 7.60% had someone living alone who was 65 years of age or older. The average household size was 2.53 and the average family size was 3.09.
The county population contained 27.00% under the age of 18, 8.50% from 18 to 24, 32.20% from 25 to 44, 21.60% from 45 to 64, and 10.80% who were 65 years of age or older. The median age was 35 years. For every 100 females, there were 96.60 males. For every 100 females age 18 and over, there were 93.60 males.
The median income for a household in the county was $51,316, and the median income for a family was $61,610. Males had a median income of $40,196 versus $29,994 for females. The per capita income for the county was $24,939. About 3.80% of families and 6.40% of the population were below the poverty line, including 6.70% of those under age 18 and 9.50% of those age 65 or over.
Politics
Olmsted has historically been a Republican-leaning county, but rapid population growth in Rochester has made it more competitive in recent years. In 2020, Joe Biden won it by nearly 11 points, the best performance of any Democratic presidential nominee since Lyndon Johnson in 1964.
Although it has trended Democratic at the presidential level, Olmsted County continues to lean Republican in state and local races, with split ticket voting becoming more common. Two of the county's three seats in the Minnesota Senate are held by Republicans, as are two of the five seats in the Minnesota House of Representatives. Since 1970, Olmsted County has voted for the DFL nominee for governor thrice: in 1974, 2018, and 2022. In 2018, then-Representative Tim Walz benefitted from high recognition in the district with a reputation at the time as a moderate. Republican nominee Doug Wardlow concurrently won the greatest number of votes in Olmsted County in the 2018 Minnesota Attorney General election.
