The Midwestern Collegiate Conference (now the Horizon League) was formed in 1979 by six NCAA Division I schools that originally dubbed themselves the Midwestern City 6, and officially the Midwestern City Conference (or MCC) soon thereafter. The charter members included Butler, Evansville, Loyola, Oklahoma City, Oral Roberts and Xavier. Marquette, an independent at the time of the league's formation, was one of two observing schools present during a preliminary meeting during the 73rd NCAA Convention in San Francisco on January 8, 1979; Creighton was the other school.

In 1985, the conference's name was altered slightly to Midwestern Collegiate Conference. Marquette announced that it will join the MCC, effective Sept. 1, 1988. The Warriors begin competition in some non-revenue sports immediately, while the remainder of the sports begin MCC play in 1989-90.

Marquette's tenure with the league was short-lived as they, along with St. Louis, announced on November 15, 1990 that they will be withdrawing from the league on June 30, 1991.

The conference again changed its name to the Horizon League on June 4, 2001, in part to avoid being confused with the Mid-Continent Conference. For most of its existence it has generally been considered one of the top mid-major conferences in the country, particularly in men's basketball.

• 1989-90: 9-5 (league), 15-14 (overall), NIT (Loss to Penn State, 57-54)

Conference Tournament Results: Lost as #4 seed to #5 Evansville, 57-66

• 1990-91: 7-7 (league), 11-18 (overall)

Conference Tournament Results: Lost as #6 seed to #3 St. Louis, 82-92

• Tony Smith - 1989-90 First Team
• Trevor Powell - 1989-90 Second Team
• Damon Key - 1990-91 Newcomer Team

• Tony Smith - 1989-90 (Weeks of Dec. 10 and Jan. 21)
• Trevor Powell - 1989-90 (Week of Jan. 2); 1990-91 (Week of Dec. 9)

• 1979-80:
• 1980-81:
• 1981-82:
• 1982-83:
• 1983-84:
• 1984-85:
• 1985-86:
• 1986-87:
• 1987-88:
• 1988-89:
• 1989-90:
• 1990-91:
• 1991-92:
• 1992-93:
• 1993-94:
• 1994-95:
• 1995-96:
• 1996-97:
• 1997-98:
• 1998-99:
• 1999-00:
• 2000-01:
• 2001-02:
• 2002-03:
• 2003-04:
• 2004-05:
• 2005-06:
• 2006-07:
• 2007-08:

• 1979-80: Evansville, Ind. (Oral Roberts)
• 1980-81: Cincinnati, Ohio (Oklahoma City)
• 1981-82: Tulsa, Okla. (Evansville)
• 1982-83: Evansville, Ind. (Xavier)
• 1983-84: Chicago, Ill. (Oral Roberts)
• 1984-85: Tulsa, Okla. (Loyola, IL)
• 1985-86: Indianapolis, Ind. (Xavier)
• 1986-87: Indianapolis, Ind. (Xavier)
• 1987-88: Indianapolis, Ind. (Xavier)
• 1988-89: Dayton, Ohio (Xavier)
• 1989-90: Dayton, Ohio (Dayton)
• 1990-91: Dayton, Ohio (Xavier)
• 1991-92: Cincinnati, Ohio (Evansville)
• 1992-93: Indianapolis, Ind. (Evansville)
• 1993-94: Indianapolis, Ind. (Detroit)
• 1994-95: Dayton, Ohio (UW-Green Bay)
• 1995-96: Dayton, Ohio (Northern Illinois)
• 1996-97: Dayton, Ohio (Butler)
• 1997-98: Green Bay, Wis. (Butler)
• 1998-99: Chicago, Ill. (Detroit)
• 1999-00: Chicago, Ill. (Butler)
• 2000-01: Dayton, Ohio (Butler)
• 2001-02: Cleveland, Ohio (Illinois-Chicago)
• 2002-03: Milwaukee, Wis. (UW-Milwaukee)
• 2003-04: Milwaukee, Wis. (Illinois-Chicago)
• 2004-05: Milwaukee, Wis. (UW-Milwaukee)
• 2005-06: Milwaukee, Wis. (UW-Milwaukee)
• 2006-07: Dayton, Ohio (Wright State)
• 2007-08: