The Wheaties box might be the most iconic of celebrity endorsement vehicles. As this history explains, what started with testimonials from all-star baseball players in the 1930s turned into a series of marketing partnerships between the General Mills cereal brand and an array of sports legends, from 1950s decathlon specialist Bob Richards to current NBA star Stephen Curry, whose pictures were emblazoned across the “breakfast of champions,” inviting grocery store shoppers to be like their heroes and buy.