The conference was formed in the fall of 1930 with charter members Aurora, Austin, Batesville, Brookville, Brownstown, Corydon, French Lick, Madison, North Vernon, Oolitic, Orleans, Osgood, Paoli, Salem, Scottsburg, and Versailles.
[1] Invitations were also made to Edinburgh, Jeffersonville, Milroy, Mitchell, New Albany, Seymour, and West Baden, but they were apparently rejected.
Osgood and Versailles would split off to form the Ohio River Valley Conference in 1952 (along with former members Milan and Rising Sun), with Vevay following the next year.
Today, in addition to the EIAC, MSC, and ORVC, former SEIC members also compete in the Hoosier Hills and Patoka Lake conferences.
The SEIC used an East-West division format from its inception until the 1953-54 school year, when the conference was reduced to 13 teams.