Pottawatomie County is a county in Kansas, United States, along the Kansas River valley northeast of Manhattan. It had a population of 25,348 at the 2020 census and covers 841 square miles (2,180 km2) of land, centred near 39°20′N 96°18′W.
Westmoreland is the county seat, and its postal code is 66549. The county has 11 incorporated cities, six unincorporated communities, and 23 civil townships. It sits in the Central time zone; its FIPS code is 20149.
Towns & Villages in Pottawatomie County
Pottawatomie County’s 11 incorporated cities range from Wamego, the largest, to one-block villages like Emmett. Six more places are unincorporated crossroads communities with no city government. A small corner of the city of Manhattan, whose main body sits in neighboring Riley County, also extends into the county’s western edge. Type key: City · seat = county seat, City = incorporated municipality, Unincorp. = unincorporated community.
| Place | Type | Township | Pop. | ZIP |
|---|---|---|---|---|
| Westmoreland | City · seat | — | — | 66549 |
| Wamego | City | Wamego | — | 66547 |
| St. Marys | City | St. Marys | — | 66536 |
| St. George | City | St. George | — | 66535 |
| Onaga | City | — | — | 66521 |
| Louisville | City | Louisville | — | — |
| Olsburg | City | — | — | 66520 |
| Havensville | City | — | — | 66432 |
| Belvue | City | Belvue | — | 66407 |
| Emmett | City | Emmett | — | 66422 |
| Fostoria | City | — | — | 66426 |
| Wheaton | City | — | — | — |
| Blaine | Unincorp. | — | — | — |
| Duluth | Unincorp. | — | — | — |
| Flush | Unincorp. | — | — | — |
| Saint Clere | Unincorp. | St. Clere | — | — |
| Swamp Angel | Unincorp. | — | — | — |
Fostoria appears twice in older lists — once as a city, once as a ZIP-only post office designation; the two are the same place. Onaga and Wheaton sit near the county’s northern edge, close enough to the Nemaha County line that mail for a few rural addresses is sorted through post offices across the border.
Townships
Pottawatomie County is organized into 23 civil townships. The table below gives each township’s 2020 population, descending, with its principal settlement where the township shares a namesake city or community.
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Wamego | 5,056 | Wamego |
| St. Marys | 2,789 | St. Marys |
| St. George | 2,629 | St. George |
| Blue | 1,802 | Rural, Kansas River bottomland |
| Mill Creek | 1,000 | Rural |
| Louisville | 735 | Louisville |
| Rock Creek | 653 | Rural |
| Pottawatomie | 499 | Rural |
| Emmett | 478 | Emmett |
| Belvue | 404 | Belvue |
| Blue Valley | 339 | Rural |
| Grant | 293 | Rural |
| Lone Tree | 239 | Rural |
| Shannon | 235 | Rural |
| Green | 188 | Rural |
| Union | 164 | Rural |
| Sherman | 126 | Rural |
| Lincoln | 124 | Rural |
| Clear Creek | 113 | Rural |
| Center | 104 | Rural |
| Vienna | 92 | Rural |
| St. Clere | 83 | Saint Clere |
| Spring Creek | 61 | Rural |
The three river townships — Wamego, St. Marys and St. George — hold most of the county’s population, since they carry both the Kansas River bottomland and its largest towns. The rural townships in the county’s north and east are almost entirely farmland.
ZIP Codes
- 66549 — Westmoreland (also serves Wheaton)
- 66547 — Wamego
- 66536 — St. Marys
- 66535 — St. George
- 66521 — Onaga
- 66520 — Olsburg
- 66432 — Havensville
- 66422 — Emmett
- 66407 — Belvue
- 66426 — Fostoria (post office box delivery only)
Louisville and Blaine have no standalone ZIP code of their own; residents there use a neighboring town’s postal code.
Geography
The Kansas River (locally the Kaw) crosses the county’s southern tier, running past St. George and Wamego, with the Big Blue River joining it near the county’s southwest corner. The northern two-thirds of the county drains through Rock Creek and Mill Creek into the Kansas River system, and the terrain rises from wide river bottomland in the south to rolling upland prairie in the north. Pottawatomie County borders Marshall County to the north, Nemaha County to the northeast, Jackson County to the east, Shawnee County to the southeast, Wabaunsee County to the south, and Riley County to the west.
Demographics
The county’s population was 25,348 at the 2020 census. Wamego and St. Marys are its two largest communities, each with more residents than any other town in the county. Median household income here runs below the Kansas median of $70,333 in county-wide terms, since the county mixes a handful of larger river towns against a broad base of small farming townships; St. Marys and Wamego post the county’s higher household incomes. With 841 square miles of land, the county’s overall density is about 30 people per square mile, concentrated heavily in the river-valley townships.
Economy & Local Life
Agriculture — row crops on the river bottomland and cattle grazing on the upland prairie — remains the backbone of the county’s rural townships. Wamego’s economy leans on retail and light manufacturing along the US-24 corridor, and its restored 1879 wooden Dutch windmill and the Oz Museum draw regional day-trip traffic. St. Marys is built around St. Marys Academy and College, a Catholic boarding school and seminary that is one of the county’s largest employers and shapes the town’s character. Tuttle Creek Lake, just over the county line in Riley County, brings weekend recreation traffic through the county’s western towns.
History
Pottawatomie County was organized in 1857, one of the original counties laid out under the Kansas Territory, and takes its name from the Potawatomi people who held a reservation here under an 1846 federal treaty before their remaining land was allotted and opened to settlement in the 1860s. St. Marys grew up around a Catholic mission established for the Potawatomi in 1848, making it one of the oldest continuously settled towns in this part of Kansas. Wamego, founded along the Kansas Pacific Railway in the early 1870s, grew into the county’s commercial center as the rail line brought grain shipping and milling to the river valley.
Getting There
US-24 runs east-west through the county, linking Wamego and St. Marys to Topeka and Manhattan. K-99 runs north-south through Onaga and Westmoreland, connecting to US-36 in Marshall County. US-75 passes along the county’s eastern edge near St. Marys.
- Manhattan — 12 miles west
- Topeka — 30 miles southeast
- Junction City — 25 miles southwest
- Seneca — 30 miles north
Manhattan Regional Airport, just across the county line in Riley County, is the nearest commercial airport.
Frequently Asked Questions
Where is Pottawatomie County?
It is in Kansas, in the northeastern part of the state, along the Kansas River northeast of Manhattan.
What is the population of Pottawatomie County?
25,348 at the 2020 census.
How big is Pottawatomie County?
841 square miles (2,180 km2) of land.
What is the county seat of Pottawatomie County?
Westmoreland is the county seat.
How many towns are in Pottawatomie County?
11 incorporated cities and 6 unincorporated communities.
What ZIP codes are in Pottawatomie County?
Ten ZIP codes serve the county, from 66407 (Belvue) to 66549 (Westmoreland).
What is Pottawatomie County known for?
Wamego’s Dutch windmill and Oz Museum, and St. Marys Academy and College, one of the largest Catholic boarding schools in the Midwest.
More counties in this state: Towns and villages in Kansas.