Lots of people know lots more than I do about what happened but I think their HC Phil Fulmer set a Bama Booster up with a recruit named Albert Means in 1999 and then turned him in to the ncaa and Bama got probation and the ncaa talked of shutting Bama football down. Lots more than that but that was the beginning. Some Tn. booster named Tn. Stud was heavily involved and the head of the SEC was also shown to be involved if I'm thinking correct.
FIFY
More here, but lots of missing details. To fill in a few gaps, Roy Kramer (Vandy grad, UT fan) was the SEC commissioner and caught wind that Means' high school coaches were trying to 'sell' their services to steer Means to a school. The SEC office sent a letter to 11 of the 12 schools (Alabama was excluded) telling them to back off Means. He ends up signing at Bama and the NCAA began snooping, eventually leveling serious allegations of pay-for-play. The FBI got involved due the amount of money involved, but even they, with subpoena power, etc., never found the money trail. The NCAA also broke their own rules by allowing a 'secret witness' (later revealed to be UT coach fulmer) to testify against Bama.
All this was an effort to shut down Bama football - orchestrated by Kramer and fulmer. It was later revealed that fulmer had been telling recruits
"Alabama will be out of business in a few years".
So yeah, tennessee, with the help of the SEC, set up Alabama. To this day, there's no proof Bama cheated wrt Means, yet we have this black stain on our history due to this fat man's fantasy.
There's a lot more to this story but that's the gist of it.
So yeah, they knew they couldn't surpass us on the field, so they decided to play dirty. This is why I hate tennessee and will never, ever wish anything but bad things for that football program.