This lecture presents various manifestations of American counterculture that were the result of the radicalization of American society in opposition to the official establishment and its mainstream culture. A special emphasis is put on the position of the “underground” culture in the 1950s and 1960s (New Left, Beat Generation, Civil Rights Movement, hipsters, the hippie “flower power” movement, folk and rock scene, Woodstock, psychedelic culture) as represented in literature, music, film and fine arts.