It goes even further back to the days of late 19th/early 20th century and artistic communes. The first time someone monetised it on a large scale was Bernays who repackaged Freud's psychoanalysis and sold it to US government and companies. His "torches of freedom" campaign tapped into the women's right movement and desire for self-expression. The tobacco industry was very pleased with the outcomes, because until then women did not smoke cigarettes. Bernays also wrote "Engineering Consent" and "Propaganda", which he renamed as Public Relations after WWII. Curtis has an interesting documentary on the subject.
Exactly. In the US culture specifically, in the XX century before the hippies, there were limited pockets of "self-expression" (discarding previous culture, really) as depicted by Henry Miller, and later the whole Beat Generation. Only after that, this tendency picked up enough steam so that the masses picked it up, in the form the Hippies movement.
