Established in 1920 and officially known as the Mississippi School and Colony for the Feebleminded, this facility opened in 1921. The name changed to Ellisville State School in 1929 after the addition of an educational program. In the 1970s, federal grants were used to establish services for persons with intellectual and developmental disabilities. By 1974, the campus had about 1,500 residents. Since then, the population of the main campus has decreased as community-based services have become more available.