In 1920, St. Thomas was one of seven charter members of the Minnesota Intercollegiate Athletic Conference (MIAC).

The Tommie football team played in the 1922 NCC season, but withdrew afterwards due to travel burdens.

The Tommies returned to the NCC in 1926, and left permanently in 1928, when the school became full members of the MIAC.

[2] In May 2019, the MIAC expelled St. Thomas from the league, due to concerns about "athletic competitive parity."

[7] The transition process was originally intended to take 5 years to complete (as opposed to the 4 years then required of schools transitioning from Division II), meaning that St. Thomas would achieve full Division I membership in 2026.