Sangamon State University (SSU) began in planning stages by the State of Illinois Board of Higher Education in 1967 (with other entities). SSU officially opened in September 1970, just south of downtown Springfield, near Lake Springfield (though classes were held in downtown Springfield until facilities were constructed. The first permanent building was Brookens Library, which was dedicated in 1976 and its first dormitories opened in 1980. Through the years, SSU was a pioneering part of higher education.

In 1995 the then governor, Jim Edgar signed a bill that merged SSU with the University of Illinois system. On July 1, 1995, SSU officially became the University of Illinois – Springfield (UIS)