Each institution in the system uses different athletic colors but the same academic hood lining pattern from the original Southern Illinois University:
Southern Illinois University Carbondale
Illinois
1869
Detailed information about the history of Southern Illinois University’s maroon and white school colors is not available at this time.
Southern Illinois University does not appear in early Intercollegiate Bureau of Academic Costume (IBAC) lists from 1927 or 1948, so the Bureau probably did not assign the university a hood lining until the late 1940s or 1950s. A list compiled by Kevin Sheard in Academic Heraldry in America (1962) described the hood lining of Southern Illinois as maroon with a white chevron, which was also how it was described in IBAC lists from 1969 and 1972.
This arrangement duplicated the hood lining the Bureau had assigned to Lafayette College in 1896, so here Southern Illinois has been reassigned a unique hood lining of maroon and white, divided vertically (“per pale”). The “division per pale” was a heraldic pattern the Intercollegiate Bureau used on rare occasions to avoid duplications of this type.