When you look at it over a long enough timeline, SEC dominance in college football was always sort of inevitable. The conference that has been home to the last eight national champions always had (at least arguably) the most raucous fan base, the fewest conflicts with the NFL, the biggest wellspring of talent dedicated solely to football. But the SEC was also beholden to tradtion, much of it so monumentally stupid that it got in the way of true dominance. Chief among these was player segregation, which is not a topic of this series, but whites-only football was not the only thing that kept the Southeastern Conference from becoming dominant. Not by a long shot.
When we last left the SEC, the great schism of the Southern Conference had just occurred. Thirteen teams -- ten which are still members of the conference (Florida, Georgia, Auburn, Alabama, Ole Miss, Mississippi State, LSU, Kentucky, Tennessee, and Vanderbilt) and three which are not (Georgia Tech, Tulane, and The University of the South (Sewanee)) -- south and west of the Appalachian Mountains decided to separate from the Southern Conference on December 8, 1932. The chancellor from Florida told the Southern Conference chairperson, Virginia Tech president Sally Miles, that the Southern Conference had simply grown too large, leading to increasingly bloated travel costs and making rivalries difficult. There were also significant divides between big state schools and smaller, private institutions.
The first defection from the new SEC was Sewanee, which was both the smallest institution and the only religious school in the new conference. "Uncompetitive" does not begin to describe Sewanee's success in its new conference: In eight seasons of SEC football, the Sewanee Tigers went 0-37. They were outscored 1,163-84. By 1940, the Episcopal leadership of the school had effectively eliminated scholarship athletics, and the school amicably left the Southeastern Conference. Sewanee currently plays in Division III. If you want to read more about Sewanee -- and, really, it's worth it -- this ESPN article on the Tigers 71 years after they had left the SEC is great.
The next to go was Georgia Tech, which left the conference in 1964. Bobby Dodd (whose name is now on the stadium) had finished his 15th season as head coach of the Yellow Jackets. There was a reason why they eventually put his name on the stadium: He was good, good enough to build Tech as one of the main SEC threats to Bear Bryant's Alabama Crimson Tide*. Dodd and Bryant did not exactly see eye to eye, either. In 1961, the two coaches feuded when an Alabama player hit a Georgia Tech player after a fair catch*, breaking the Tech player's nose. Bryant refused to suspend the player, despite Dodd's protestations. Dodd got his revenge in 1962, when Georgia Tech beat Alabama 7-6 to knock the top-ranked Tide* out of the national championship race.
* -- Roll Tide
But Dodd's issue with the conference in general, and Alabama** in particular, stemmed from a still-festering SEC problem: Oversigning. At the time, the NCAA operated under a 140 scholarship rule: A Division I university could award up to 140 total scholarships for football and basketball in a given year, and could sign up to 45 players per year to fill those spots. Obviously, this meant that a football program could have approximately 120 players in an era where players rarely transferred and never left early for the NFL. Dodd signed 30-35 players a season to keep his roster full. Alabama, which already did not give a damn about basketball**, signed the full alottment of 45 to the football program, then cut to 140 players in the summer. This effectively kept the cut players off a college roster for a year.
** -- Roll damn Tide
Dodd, who had become Tech's athletic director in 1950, demanded the conference reduce the 45-scholarship yearly allotment to 32 new full rides per year. He brought his proposal to the SEC meetings, where he needed seven of the SEC presidents to vote in favor of the reduced scholarship limit. And Dodd, who had explicitly told the presidents that Georgia Tech would leave the conference if the 32-scholarship rule did not pass, thought he had a strange ally: Bear Bryant, who guaranteed to Dodd that Alabama's president would give him the seventh vote he needed.
When the vote came, Alabama voted no, because Bear Bryant was Bear Bryant, son. One vote short, Georgia Tech's president walked to the podium and gave notice that Georgia Tech was out. The SEC was down to 11 teams.
Tulane, which had fielded the first black athlete in the SEC, was the next to go. On October 15, 1949, the Green Wave were the nation's No. 4 team as they went into a pseudo-Game of the Century with No. 1 Notre Dame. The Irish won 46-7, and the program has literally never recovered. Six weeks later, despite an SEC title, Tulane was left out of the Sugar Bowl in favor of arch rival LSU. Soon after the season, the school's president announced a long-feared plan to deemphasize sports in general and football in particular. There were strict new academic standards: A student athlete would have to be in the top half of his high school class to get an athletics scholarship, a standard not followed by the rest of the conference. There would also be fewer scholarships available for athletes. The higher standards, coupled with a dearth of scholarships -- one year, the Green Wave had just 38 football scholarships available -- made competing in the SEC impossible.*** The program's head coach, the legendary Henry Frnka, immediately quit when the new academic and scholarship standards were announced. The next three coaches were almost immediately fired. Tulane became uncompetitive in the SEC -- the Green Wave went winless in 1962 -- and the university jumped ship in 1966, just as it was stopping the de-emphasis program and preparing to move into the Superdome.
*** -- There was some talk at the time of a "Southern Ivy League" with Tulane joining Duke, Rice, SMU, Vanderbilt, and other academically-inclined institutions, but Rice and SMU were happy in the SWC and Vandy wasn't dumb enough to leave the SEC.
With Tulane's departure, the SEC became a ten-team league. It would remain that way until 1991, when an obscure 1984 Supreme Court ruling forced the conference's reluctant grasp on tradition to give way, opening the floodgates and setting off the first huge round of nationwide realignment since the 1920s.