THE HISTORY OF ROCK MUSIC. What is Rock Music? (Documentary): We love rock ’n’ roll: well, it’s hard not to, with its sexy, totally exhilarating back story, and the way it continues to evolve and remain relevant. Almost 70 years after it burst onto the scene in the United States, the jury’s still out on who actually invented it. The truth is, rock ’n’ roll is a mash-up of genres that aligned at the perfect time, just as people emerged from the trauma of the Second World War craving a complete break from the recent past, and with money to spend.