I never understood the Rams moving to St Louis in the first place.
Readers Digest version: The owner, Carroll Rosenbloom, died suddenly. His wife (a lounge singer who was on husband #5 or 6 with Rosenbloom) inherited a 70% stake in the team. His children inherited the rest. She knew nothing about football. She made a series of bone-head moves that included firing popular people in the front office...including Rosenbloom's son. (It would be equivalent of firing Michael.) She fired the Rams' version of Keim, who was well-liked, and hired a general manager who quickly alienated the fans. The players disliked her. The fans HATED her.
The team was not playing well and the fans refused to buy tickets for a team owned by Frontiere. (She remarried within a year of Rosenbloom's death.) She was from St Louis and saw the chance to make a PILE of money by moving the team. She wasn't going to stay in Anaheim with people chanting obscenities at her every time she walked onto the field.
There was a prolonged legal battle with So Cal fans and officials trying to keep the team. The courts ruled in favor of the owner. Paul Taglaibue gave her the OK despite pleas from fans. She packed up and left for greener pastures... where the fans didn't hate her. Lucky for her Kurt Warner and the Greatest Show on Turf came along and saved the franchise.