Polk County, Nebraska
Polk County is a county in the U.S. state of Nebraska. As of the 2020 United States census, the population was 5,214. Its county seat is Osceola. The county was formed in 1856, and was organized in 1870. It was named for President James K. Polk. In the Nebraska license plate system, Polk County is represented by the prefix 41 (it had the 41st-largest number of vehicles registered in the county when the license plate system was established in 1922).