Waterloo is a town in Grant and Smithfield townships, DeKalb County, Indiana, United States. The population was 2,242 at the 2010 census. History Waterloo was laid out in 1856 when the railroad was extended to that point. It was likely named after Waterloo, in Belgium. The Waterloo Community Mausoleum was added to the National Register of Historic Places in 2014. Geography Waterloo is located at . According to the 2010 census, Waterloo has a total area of , all land. A nearly complete mastodon skeleton discovered near Waterloo in 1888 is displayed at the Carnegie Museum of Natural History in Pittsburgh. Demographics 2010 census As of the census of 2010, there were 2,242 people, 809 households, and 577 families living in the town. The population density was . There were 942 housing units at an average density of . The racial makeup of the town was 95.3% White, 0.5% African American, 0.1% Native American, 1.7% from other races, and 2.4% from two or more races. Hispanic or Latino of any race were 3.8% of the population. There were 809 households, of which 42.5% had children under the age of 18 living with them, 48.1% were married couples living together, 16.8% had a female householder with no husband present, 6.4% had a male householder with no wife present, and 28.7% were non-families. 23.4% of all households were made up of individuals, and 7.5% had someone living alone who was 65 years of age or older. The average household size was 2.77 and the average family size was 3.19. The median age in the town was 31.5 years. 30% of residents were under the age of 18; 10.1% were between the ages of 18 and 24; 29.1% were from 25 to 44; 22.9% were from 45 to 64; and 8% were 65 years of age or older. The gender makeup of the town was 50.6% male and 49.4% female. 2000 census As of the census of 2000, there were 2,200 people, 832 households, and 584 families living in the town. The population density was . There were 898 housing units at an average density of . The racial makeup of the town was 95.50% White, 0.23% African American, 0.45% Native American, 0.18% Asian, 2.82% from other races, and 0.82% from two or more races. Hispanic or Latino of any race were 3.68% of the population. There were 832 households, out of which