1963: The Year of the Revolution by Robin Morgan and Ariel Leve
In the course of human history, teenagers are a fairly recent invention. Of course, humanity’s always gone through adolescence, but as a social construct, young adulthood was really developed after World War II, when post-war prosperity meant that teenagers had money—and, therefore, agency—for the first time en masse. Add to that the baby boom, and you’ve got yourself prime conditions for changing the culture.