Allen Ginsberg rose to prominence on the San Francisco scene in the 1950’s, a decade before the summer of love. He was a part of the beat generation who were a group of poets that began rejecting traditional American customs both in their works and in the way they lived their lives. The beat generation shared many of the same values through their spirituality, openness, and experimentation with drugs as did the hippies who would soon follow the beat generation to San Francisco. Ginsberg transitioned into the hippie movement and became something of an idol to many of the young hippies who had read his poetry. He was a strong activist for freedom of speech, gay rights, and ending the war in Vietnam. Below are photos of Ginsberg at the Human Be-In. 
Ginsberg at the Human be-in 1/67
Ginsberg reading his most famous poem howl can be found at this link:
The World They Imagined 