Why did prize fighting, horse racing, and baseball become the first three professional sports in the United States?
This is opinion of course, but all three of those sports started at a very local, informal level, and as they grew in popularity, they turned into professional leagues as they went. That is, these were grass roots sports that caught on slowly. What really turned the corner for all three of them in terms of being national pastimes, to me, was the invention and popular sale of the radio in the 1920s. All three of these are easily broadcast over the radio to mass audiences who didn’t have the money or transportation to get to these matches/races/games. For quite a while, crowding around the one radio set in the neighborhood on a Saturday night listening to Max Baer and Jimmy Braddock pound away, or to hear Seabiscuit and War Admiral race during the 30’s, or Babe Ruth and Lou Gehrig become champions on the airwaves as Yankees in the 20s, was what people did on the weekends. The radio took these sports to the entire country, and aided in the formation of professional leagues and association
