The history of modern popular music - rock and roll is not really a sufficient umbrella anymore - started in the late ‘40s and early ‘50s with the earliest forms of rock and roll from New Orleans.
BY the ‘50s, with the help of radio, it had spread to white youth and in the ‘60s it came to define youth culture, the restless, teeming baby boomers who carried it to the far corners of the globe.
The Soviet Union collapsed for many reasons, mostly political and economic, but also cultural: the Politburo hated rock and roll but it couldn't hold the music or its trappings back: at one point, you could go to the USSR or any of the Eastern Bloc countries with a suitcase full of Levis and basically pay for your trip.