- Osceola is a city in Clarke County, Iowa, United States. It is located in the southern part of the state, about 40 miles south of Des Moines. The city has a population of approximately 4,876 residents as of the 2020 census. Osceola is known for its historic downtown area, which features many well-preserved buildings from the late 19th and early 20th centuries. The city is also home to the Clarke County Courthouse, which is listed on the National Register of Historic Places. Osceola offers a variety of recreational opportunities, including parks, golf courses, and a nearby lake for boating and fishing.