Originally inhabited by the Muscogee people, by the 1840s three small settlements existed nearby: Plains of Dura, Magnolia Springs, and Lebanon. As railway access expanded into the region in response to increased cotton farming, these settlements coalesced closer to the new railway location. As businesses rapidly developed, local businessmen successfully petitioned the State Legislature to shorten Plains of Dura to Plains. Plains was subsequently incorporated in 1896. Plains continued to experience growth fueled by cotton cultivation well into the early twentieth century. A substantial school and the pioneering Wise Sanitarium were both built in the 1920s. Despite differentiation into peanut cultivation, the Great Depression deprived the community of much of its prosperity. Plains remained a quiet Southern town until Jimmy Carter rose to political prominence in the 1970s, eventually becoming President of the United States from 1977–1981. During the 1976 Presidential Election and for many years afterwards, Plains saw a giant influx in tourism. Nearly ten thousand people would pour into the community daily.
As of the census of 2000, there were 637 people, 215 households, and 136 families residing in the city. The population density was 780.0 people per square mile. There were 244 housing units at an average density of 298.8 per square mile. The racial makeup of the city was 38.62% White, 59.81% African American, 1.26% from other races, and 0.31% from two or more races. Hispanic or Latino of any race were 2.83% of the population. There were 215 households out of which 25.6% had children under the age of 18 living with them, 36.7% were married couplesliving together, 24.2% had a female householder with no husband present, and 36.3% were non-families. 34.9% of all households were made up of individuals and 19.5% had someone living alone who was 65 years of age or older. The average household size was 2.50 and the average family size was 3.31. In the city, the population was spread out with 24.6% under the age of 18, 8.5% from 18 to 24, 16.5% from 25 to 44, 20.3% from 45 to 64, and 30.1% who were 65 years of age or older. The median age was 45 years. For every 100 females, there were 69.0 males. For every 100 females age 18 and over, there were 58.9 males. The median income for a household in the city was $26,719, and the median income for a family was $29,375. Males had a median income of $24,375 versus $16,406 for females. The per capita income for the city was $11,602. About 22.2% of families and 25.6% of the population were below the poverty line, including 47.2% of those under age 18 and 17.3% of those age 65 or over.
