Osceola County

county in Iowa, United States

Key facts

Country: United States
State: Iowa
Founded: January 15, 1851 (created), January 1, 1872 (organized)
Named after: Osceola
Seat: Sibley
Largest city: Sibley
Total: 399.396 sq mi (1,034.43 km )
Land: 398.687 sq mi (1,032.59 km )
Water: 0.709 sq mi (1.84 km ) 0.18%
Estimate 2025: 5,980
Density: 15.53/sq mi (5.997/km )
Time zone: UTC−6 ( Central )
Summer dst

Article

Osceola County (/ˌɒsiˈoʊlə/ OSS-ee-OH-lə) is a county located in the U.S. state of Iowa. As of the 2020 census the population was 6,192, and was estimated to be 5,980 in 2025, making it the fifth-least populous county in Iowa. It is named for Seminole war chief Osceola. The county seat and the largest city is Sibley, named for H. H. Sibley of Minnesota.

History