Dupo is a member of the Cahokia Conference in all sports except football, where it competes in the Prairie State Conference starting with the 2017 season.[2] Carlyle will also not be a member for football starting in 2020 due to moving from 11-man football to 8-man football.[3]
Two schools, Valmeyer and Steeleville, were added for the 2006–07 season. The addition split the conference into two divisions, the Mississippi and the Kaskaskia. Salem was admitted to the conference in 2017, joining the Mississippi Division.
Expansion and realignment occurred starting with the 2022–23 school year. Chester, Okawville, Roxana, Sparta and East Alton-Wood River all joined the Cahokia.[4] After all schools join, The conference would then realign into three divisions:
Mississippi Division - Breese (Central), Columbia, Freeburg, Roxana, Salem and Wood River (East Alton-W.R.)
Kaskaskia Division - Dupo, Lebanon, Marissa, New Athens, Steeleville, Valmeyer
Illinois Division - Carlyle, Chester, Okawville, Red Bud, Sparta and Trenton (Wesclin)
Each year a conference champion is determined in each division for volleyball, boys and girls basketball, baseball, and softball by each division member playing round-robin home and away. The team with the best win–loss record is the champion.
For boys and girls golf and boys soccer one champion is determined by round–robin play, with each school in the conference playing each other once. The team with the best win–loss record is the champion.
Cross country and track & field for boys and girls each have one champion determined by the winner of each sport's conference meet. The scholastic bowl champion is the winner of the conference tournament.
Like golf and soccer, the conference football championship is determined based on round–robin play. However, only seven teams (the Mississippi division and Dupo) field football teams. As noted above, Carlyle will begin 8-man play in 2020 moving the conference to 6 schools for the short-term.
There is no cross-over for conference play due to the size discrepancy between schools in the Mississippi Division and schools in the Kaskaskia Division.
No other small school athletic conference in the state of Illinois has claimed as many state baseball championships as the Cahokia Conference. The list of championships by current member teams includes 7 years (1979, 1981, 1986, 1987, 1989, 1996, and 2007), as well as 9 runner-up performances (1948, 1956, 1978, 1990, 1993, 2002, 2006, 2008, and 2009), and two third-place finishes (2010 & 2014).
In the 2005 state volleyball tournament Breese Central defeated Columbia in the championship match. This was the first time in IHSA Volleyball history that two teams from the same conference met in the title match. Ironically, the conference champion of 2005 was Freeburg, which had moved to class AA and won the first ever AA regional for a school from this conference.
