The site of present-day Pawnee City was designated as the county seat on November 4, 1856, and the townsite was platted in the spring of 1857.

[8] On August 9, 1881, two-thirds of downtown Pawnee City was destroyed by a fire.

[5][6] According to the United States Census Bureau, the city has a total area of 1.21 square miles (3.13 km2), all land.

[9] At the 2010 census there were 878 people, 425 households, and 210 families living in the city.

At the 2000 census there were 1,033 people, 474 households, and 264 families living in the city.

The racial makeup of the city was 99.13% White, 0.19% Native American, 0.10% Asian, and 0.58% from two or more races.

[3] Of the 474 households 22.4% had children under the age of 18 living with them, 47.3% were married couples living together, 7.2% had a female householder with no husband present, and 44.3% were non-families.