Peterson is a city in Clay County, Iowa, United States. The population was 322 in the 2020 census, a decline from 372 in 2000. History The first settlement was made at Peterson in 1856. In 1862, a fort was built in Peterson by settlers to defend against anticipated Dakota attacks during the Dakota War, though the fort was never attacked. The blockhouse from this fort still stands near its original location at the corner of Second and Park. Peterson was platted in 1881 when the railroad was extended to that point. The city was named for Adlie Peterson, an early settler. Geography Peterson's longitude and latitude coordinatesin decimal form are 42.918490, -95.341502.It is situated near the Little Sioux River. According to the United States Census Bureau, the city has a total area of , all land. Demographics 2010 census As of the census of 2010, there were 334 people, 156 households, and 95 families residing in the city. The population density was . There were 196 housing units at an average density of . The racial makeup of the city was 99.4% White and 0.6% from two or more races. Hispanic or Latino of any race were 2.1% of the population. There were 156 households, of which 24.4% had children under the age of 18 living with them, 48.1% were married couples living together, 7.7% had a female householder with no husband present, 5.1% had a male householder with no wife present, and 39.1% were non-families. 37.2% of all households were made up of individuals, and 25% had someone living alone who was 65 years of age or older. The average household size was 2.14 and the average family size was 2.78. The median age in the city was 50.5 years. 19.5% of residents were under the age of 18; 4.8% were between the ages of 18 and 24; 18.6% were from 25 to 44; 30.9% were from 45 to 64; and 26.3% were 65 years of age or older. The gender makeup of the city was 47.9% male and 52.1% female. 2000 census As of the census of 2000, there were 372 people, 181 households, and 106 families residing in the city. The population density was . There were 200 housing units at an average density of . The racial makeup of the city was 100.00% White. Hispanic or Latino of any race were 1.08% of the population. There