The history of the backwards cap...
Actually the backwards cap is a baseball thing. The hat, that many players in sports wear today originate from the baseball cap which was designed at the turn of the century to block the sun out of the players eyes in the American born sport of Baseball.
The unique style of the brim and the cap are completely Baseball's own creation. As baseball evolved the caps evolved too, and to protect players from balls thrown over 90mphs players started to wear helmets.
One of players that needed a helmet the most was the catcher, however because the catcher wears a facemask to protect his face from a errant pitch or the swing of a bat, the helmet with brim attached had to be turned backwards.
Thus, the backwards cap was born, and ever since baseball fans, sports fans, and players alike have been wearing them that way. Who knows when exactly the necessity of having a backwards cap become in vogue and why it was considered stylish, or who started doing it first but it was born in baseball.