There are three state universities in Iowa. Iowa State University (ISU), University of Iowa (UI) and Universirty of Northern Iowa (UNI). I grew up in a house of UI fans, but we rooted for ISU and UNI too - afterall, they are all Iowa schools. Then I went to ISU and my little brother and sister went to UNI now my parents are way more likely to be wearing yellow with red (ISU) or purple (UNI) than with black (UI).
Over the years I have shied away from rooting for UI, not because of the school or teams, but because of the fans, not all of the fans, but that select few that are intolerable. The Hawkeye football team is doing really well this year and Hawkeye fever is sweeping the state and has reached my It's Easy Being Green business on Etsy. Here's the first three custom order ones I've made; I have two more football specific UI ones I am working on.