*Heartland Christian School, located in Council Bluffs, co-ops with St. Albert Catholic for baseball, football, cheer, and softball.

In 2013, Corning and Villisca entered a joint operation agreement and are known as the Southwest Valley Timberwolves, competing in the Pride of Iowa Conference.

For all other sports, enrollment numbers from grades 10-12 are used to determine classes for the current school year.

The 1930 track meet at Red Oak was the first official event, with Shenandoah claiming the first title in league history.

The conference was known as the Hawkeye Eight until 1993 when Kuemper Catholic and Denison, recently partnered with Schelswig, joined.

In 2017, the Missouri River Conference sent letters inviting both Lewis Central and Glenwood to join.