# Olmsted County, Minnesota *County in southeastern Minnesota, seat Rochester* Olmsted County is a county in the U.S. state of [[Minnesota]]. The 2020 census counted 162,847 residents, and the 2025 estimate was 166,731, which places it seventh among the state's counties by population. Rochester is both its largest city and its county seat, and the county belongs to the Rochester metropolitan area.[^1] The county was formed on February 20, 1855, from parts of Rice, Wabasha and Fillmore counties. Its boundaries have not changed since. It takes its name from David Olmsted (1822–1861), who sat on the first territorial council and served as St. Paul's fourth mayor.[^2] Rochester sits at the center of the county and meets farmland directly, with no suburban buffer between them.[^3] At the presidential level the county has moved toward Democratic nominees, while in state and local races it still leans Republican.[^4] ## History The federal government established the Wisconsin Territory effective July 3, 1836. That territory lasted until 1848, when its eastern portion became the state of Wisconsin. The federal government then organized the [[Minnesota Territory]], effective March 3, 1849. In October of that year the new territorial legislature created nine counties.[^5] Wabasha County, one of those nine, gave up land in 1853 when Fillmore and Rice counties were formed. On February 20, 1855, parts of Rice, Wabasha and Fillmore counties were split off to form Olmsted County. Rochester, which was platted the same year, became the county seat.[^2] ## Geography Olmsted County's urban and rural areas meet with no transition zone between them. Rochester, the state's third-largest city at roughly 123,000 people, lies in the Zumbro River valley in the middle of the county. Beyond the valley the land is farmland with small agricultural communities and no directly adjacent suburbs, apart from a small amount of recent urban growth. Stewartville is the county's second-largest city, with about 6,000 residents.[^3] Three rivers drain the county, and all of them flow to the Mississippi. The Zumbro runs north through the west-central portion into Wabasha County. The Whitewater runs northeast out of the county's northeast part into Winona County. The Root runs east-southeast across the lower part of the county into Fillmore County. The terrain is low rolling hills cut by drainage gullies, with occasional buttes, and it slopes toward the east and north. The highest point is a hill 7.5 miles (12.1 km) west of Stewartville, at 1,380 feet (420 m) above sea level.[^6] According to the [[United States Census Bureau]], the county covers 654.754 square miles (1,695.81 km²) in total. Of that, 653.509 square miles is land and 1.245 square miles (0.19%) is water. By total area it ranks 46th among Minnesota counties. Olmsted is one of only four Minnesota counties with no natural lakes; the other three are Mower, Pipestone and Rock.[^7] Transit providers serving the county are Jefferson Lines, Rochester City Lines and Rochester Public Transit. Its major highways include Interstate 90, U.S. Highways 14, 52 and 63, and Minnesota State Highway 30.[^8] ## Demographics The 2020 census counted 162,847 residents, with a median age of 37.1 years. Of those residents, 23.7% were under 18 and 15.9% were 65 or older.[^9] The 2024 American Community Survey estimated 67,723 households, averaging 2.41 persons each. It put the median household income at $92,942 and found about 5.9% of residents at or below the poverty line. The same survey estimated a 69.6% employment rate. It found that 95.7% of the population held a high school diploma and 51.6% held a bachelor's degree or higher. The county had 73,143 housing units, an average of 111.92 per square mile.[^10] The 2024 estimate put the population at 166,424, a density of 254.66 inhabitants per square mile. By race, residents were 80.8% White (75.4% non-Hispanic White), 8.6% African American, 0.5% Native American, 7.1% Asian, 0.1% Pacific Islander and 2.9% of two or more races. Hispanic or Latino residents of any race made up 6.3%.[^10] Respondents could report up to two languages, so the shares total more than 100%. English was reported by 88.5%, Spanish by 3.1%, Asian and Pacific Islander languages by 3.5%, Indo-European languages by 2.6%, and other languages by 2.3%.[^10] In the second quarter of 2025 the county's median home value was $380,616. The real estate website Zillow reported an average home price of $337,521 as of November 30, 2025.[^11] ## Politics The county has historically leaned Republican, but rapid growth in Rochester has made it more competitive. Joe Biden carried the county by nearly 11 points in 2020. That was the strongest result for a Democratic presidential nominee there since [[Lyndon Johnson]] in 1964.[^4] Below the presidential level the county still tends Republican, and split-ticket voting has become more common. As of the cited revision, Republicans held two of the county's three seats in the [[Minnesota Senate]]. They also held two of its five seats in the [[Minnesota House of Representatives]].[^12] Since 1970 the county has backed the DFL nominee for [[governor]] three times, in 1974, 2018 and 2022. In 2018, [[Tim Walz]], then a Representative, benefited from high name recognition in the district and a reputation at the time as a moderate. In the same year the Republican nominee, Doug Wardlow, received the most votes in the county in the election for [[Minnesota Attorney General]].[^12] ## Education The following K-12 school districts serve the county. Districts marked partial extend only partly into Olmsted County.[^13] - Plainview-Elgin-Millville (ISD #2899, partial) - Byron (ISD #531) - Chatfield (ISD #227) - Dover-Eyota (ISD #533) - Hayfield (ISD #203, partial) - Kasson-Mantorville (ISD #204, partial) - Pine Island (ISD #255, partial) - Rochester (ISD #535) - St. Charles (ISD #858, partial) - Stewartville (ISD #534) - Zumbrota-Mazeppa (ISD #2805, partial) ## Communities The county has eight cities: Byron, Chatfield (part), Dover, Eyota, Oronoco, Pine Island (part), Rochester (the county seat) and Stewartville. High Forest and Marion are census-designated places.[^14] Its sixteen unincorporated communities are Chester, Cummingsville, Danesville (part), Douglas, Genoa, Judge, Pleasant Grove, Post Town, Potsdam, Predmore, Ringe, Rock Dell, Salem Corners, Shanty Town, Simpson and Viola.[^14] The county has eighteen townships: Cascade, Dover, Elmira, Eyota, Farmington, Haverhill, High Forest, Kalmar, Marion, New Haven, Orion, Oronoco, Pleasant Grove, Quincy, Rochester, Rock Dell, Salem and Viola.[^14] ## Notes [^1]: Wikipedia contributors, *Olmsted County, Minnesota*, lead section (revision 1375304307, retrieved 2026-10-25) — 2020 census and 2025 estimated population, population rank, county seat, metropolitan area. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^2]: Wikipedia contributors, *Olmsted County, Minnesota*, History section (revision 1375304307, retrieved 2026-10-25) — 1853 partition of Wabasha County, February 20, 1855 creation, county seat, namesake, unchanged boundaries. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^3]: Wikipedia contributors, *Olmsted County, Minnesota*, Geography section (revision 1375304307, retrieved 2026-10-25) — urban–rural character, Rochester and Stewartville populations. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^4]: Wikipedia contributors, *Olmsted County, Minnesota*, Politics section (revision 1375304307, retrieved 2026-10-25) — historical partisan lean, 2020 presidential margin, comparison with 1964. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^5]: Wikipedia contributors, *Olmsted County, Minnesota*, History section (revision 1375304307, retrieved 2026-10-25) — Wisconsin Territory (1836–1848), Minnesota Territory (March 3, 1849), nine original counties (October 1849). https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^6]: Wikipedia contributors, *Olmsted County, Minnesota*, Geography section (revision 1375304307, retrieved 2026-10-25) — rivers, terrain, highest point. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^7]: Wikipedia contributors, *Olmsted County, Minnesota*, Geography section (revision 1375304307, retrieved 2026-10-25) — Census Bureau area figures, area rank, absence of natural lakes. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^8]: Wikipedia contributors, *Olmsted County, Minnesota*, Geography section, Transit and Major highways subsections (revision 1375304307, retrieved 2026-10-25) — transit providers and highways. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^9]: Wikipedia contributors, *Olmsted County, Minnesota*, Demographics section, 2020 census subsection (revision 1375304307, retrieved 2026-10-25) — 2020 population, median age, age shares. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^10]: Wikipedia contributors, *Olmsted County, Minnesota*, Demographics section (revision 1375304307, retrieved 2026-10-25) — 2024 American Community Survey and 2024 estimate figures, languages. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^11]: Wikipedia contributors, *Olmsted County, Minnesota*, Demographics section (revision 1375304307, retrieved 2026-10-25) — 2025 median home value and Zillow average price. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^12]: Wikipedia contributors, *Olmsted County, Minnesota*, Politics section (revision 1375304307, retrieved 2026-10-25) — state and local lean, legislative seats, DFL gubernatorial wins since 1970, 2018 gubernatorial and attorney general results. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^13]: Wikipedia contributors, *Olmsted County, Minnesota*, Education section (revision 1375304307, retrieved 2026-10-25) — K-12 school districts and ISD numbers. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota [^14]: Wikipedia contributors, *Olmsted County, Minnesota*, Communities section (revision 1375304307, retrieved 2026-10-25) — cities, census-designated places, unincorporated communities, townships. https://en.wikipedia.org/wiki/Olmsted_County,_Minnesota