In 1894, a chemistry professor at Vanderbilt helped found an organization called the Southern Intercollegiate Athletic Association. That forerunner of the modern conference began with seven member institutions — Alabama, Auburn, Georgia, Georgia Tech, North Carolina, Sewanee, and Vandy. A year later, Clemson, Cumberland, Kentucky, LSU, Mercer, Mississippi State (then known as Mississippi A&M), Ole Miss, the University of Nashville, Rhodes College (then known as Southwestern Presbyterian), Tennessee, Texas, and Tulane joined in on the fun.
By 1921, the SIAA had grown into a 30-school monstrosity. So 14 of those SIAA schools met in Atlanta on February 21st of that year to discuss setting up a new, smaller conference. Part of the reason — schools wanted to play their conference rivals more often, which was impossible in a 30-team league. Also, the SIAA’s presidents couldn’t agree on freshman eligibility or whether or not athletes should be allowed to make money playing summer baseball.
Looks like things started out as Super Conferences. Some interesting historical background and other insights
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