Before the dawn of the new decade, radical subcultures had emerged within the American social order. The psychedelic fad of the mid 60s bloomed into mainstream with the 1966/67 "summers of love" and the1969 Woodstock Music and Art Fair, and exposed to the world a reactionary lifestyle based on peace, drug experimentation, free love and communal living that had a particularly strong impact on the decade to follow.
Hippies borrowed clothing from folk cultures, used strong colors, flamboyant styles and a love of humble items such as jeans and other tattered and embellished street wear items to proclaim their non-conformism and thirst from freedom. Using anti-fashion as yet another form of protest against the establishment, they utilized clothing to tell of their plight for social equality and diversity.
Although their behavior was appalling to the mainstream audience, their styles soon entered the mainstream and the world of high fashion. Unlike the previous gravitational dictate from the high fashion world to the masses, the hippie influence "trickled up" and entered the middle classes in various ways. Their music, ideals and garments were disseminated through popular culture but the hippie styles were also removed from their political surroundings and were emulated by designers such as Saint Laurent, Giorgio di' Sant Angelo and Kenzo. Ethnicity also became fashionable and entered the fashionable world through the traditional "trickled down" pathway. http://dept.kent.edu/museum/exhibit/70s/jeans.htmlAnother reason the clothes were popular--they were cheap. Thrift shop & ethnic clothes were affordable--& a good alternative to the hideous preppy look. Then the fashion designers paid attention. The same thing happened with punk & grunge "fashions."
The hippie look has, indeed, been back. Hiphugging bellbottoms & halter tops on the younger set, ethnic details for the oldsters.