I'm not sure what you're driving at here;
ISU has played major conference football as long it has existed. From the Mo Valley to the Big Six, 8 and XII, ISU has been in power conferences.
You do realize that Iowa's first varsity game was against Grinnell and that Iowa occupied the Mo Valley (with ISC) when it was a power conference, right? If your argument is that ISU hasn't been in power conferences from the beginning you're wrong.
The mo valley didn't exist until 1907 therefore isu has not been playing cfb in a major confirm "since the 1800s " sorry but ISUer has issues with honesty and embellishment.