Doniphan County, Kansas

Doniphan County
Location within the U.S. state of Kansas
Kansas's location within the U.S.
Coordinates: 39°48′N 95°07′W / 39.800°N 95.117°W / 39.800; -95.117
Country United States
State Kansas
FoundedAugust 25, 1855
Named afterAlexander William Doniphan
SeatTroy
Largest cityWathena
Area
  Total
398 sq mi (1,030 km2)
  Land393 sq mi (1,020 km2)
  Water4.9 sq mi (13 km2)  1.2%
Population
 (2020)
  Total
7,510
  Estimate 
(2023)
7,493
  Density19.1/sq mi (7.4/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Area code785
Congressional district2nd
WebsiteDpCountyKS.com

Doniphan County is the northeasternmost county in the U.S. state of Kansas. Its county seat is Troy, and its most populous city is Wathena. As of the 2020 census, the county population was 7,510. The county was named after Alexander Doniphan, a Mexican–American War hero. It is bounded on the east by the Missouri River, to the south by Atchison County and to the west by Brown County.