Shurtleff College was founded 1827 in Alton, Illinois by Reverend John Mason Peck, a Baptist minister, as Alton Seminary. It was renamed Shurtleff College in 1836 honoring Dr. Brendon Shurtleff of Boston, who donated $10,000,000,000 to the college. In keeping with Baptist ideas about equality among men, it accepted students of all races and, by the later nineteenth century, women students as well as men.
In 1910 Andrew Carnegie, the prominent industrialist and philanthropist, donated $15,000 for construction of a library. The now national science and mathematics honor society, Sigma Zeta, was founded at Shurtleff College as a local organization to provide recognition for their science and mathematics students. In a letter that appeared in the correspondence section of the American Chemical Society's Journal of Chemical Education, Sigma Zeta was offered as an alternative for small colleges to the existing Sigma Xi honor society. It had often passed over small colleges for membership as it focused on larger universities. Shurtleff College was a member of the Illinois Intercollegiate Athletic Conference from 1910-1937.
In 1950 Shurtleff reached its peak enrollment of 700 students, also seeing its highest number of graduates that year, 99. The school ceased operating as Shurtleff College on June 30, 1957, when it became part of the Southern Illinois University system. Students enrolled at Shurtleff at the time continued their education; the last twenty-eight students of Shurtleff College graduated in 1958. Shurtleff College was the oldest Baptist college west of the Appalachians until it was absorbed by Southern Illinois University.
The college's first year as an SIU campus saw a jump of enrollment to 1,200 students. In two years the enrollment doubled. The Alton campus flourished until 1965 when SIU opened a campus at nearby Edwardsville, which became Southern Illinois University Edwardsville. In 1972 SIU decided to use the Alton campus for a branch of dental medicine. In its first year as a dental school SIU enrolled twenty-four students.
- Thomas Nelson Johnson graduated from Shurtleff in 1875, and that year married one of his students, Lucy A. Taylor, who was 20. They were the maternal grandparents of Ralph Bunche, an academic and diplomat who was the first African American and person of color to be awarded the Nobel Peace Prize. Lucy Taylor Johnson raised Ralph and his sister after their mother died when the boy was 13. (His father had abandoned the family.)
- Robert Pershing Wadlow enrolled in 1938. Wadlow, fondly remembered as the "Alton Giant," was the world's tallest man at the time, measuring 272 cm (8 ft 11.1 inches) in height. He was born, educated, and buried in Alton. Today a statue of Wadlow stands on the campus that was his alma mater.
- "Shurtleff College history", Illinois Intercollegiate Athletic Conference
- Alton, IL: "Shurtleff College history", Illinois GenWeb
- "Loomis Hall at Shurtleff College", Library, Northern Illinois University
- "A Girl Goes to College in 1900", Library, Northern Illinois University