The hippie movement coincided with the escalation of the Cold War. Many young people had a fatalistic attitude about the future. And it was strictly a young people's movement. They expected a nuclear holocaust that would destroy civilization, if it didn't in fact annihilate all life on the planet. The Americans and the Soviets were stockpiling atomic weapons in what seemed like a suicidal arms race. And then the Chinese Communists developed their own atomic weapons. It seemed only logical that these missiles and bombs would eventually be used. There had never been a time when nations engaged in arms buildups and mobilization and then didn't go to war. Many people were building bomb shelters in their backyards. Many were fleeing from the cities to the suburbs, hoping to put at least a little distance between themselves and the prime targets. Everybody knew that Vietnam was just one theater of the Cold War. The Communists could start such wars all over the world because there was so much poverty and Communism promised a solution. The hippies were opposed to the state of eternal war that seemed to be threatening the world. They wanted to opt out of the madness that seemed to be gripping humanity. They were not in sympathy with the Communists, but they were not in sympathy with their own government either. They believed that something positive could be done if their leaders really wanted to. Eventually the young people forced the American government to get out of Vietnam, where it had no business being in the first place. The so-called "Domino Effect" did not occur. The world is far from being stabilized yet, and there are still plenty of atomic missiles in good working condition, many of them in new locations such as North Vietnam, Israel, and Pakistan.
I agree with most of what has been said in the posts above, particularly that the hippie movement was part of a "perfect storm" of desire for social and political reform following the end of WWII and the materialistic 1950s. One of the things that led to the movement was the fact that the 50s seemed like a prosperous time and yet racism was still rampant, making it hypocritical to say this was a "good time" in American history. I think, out of that complacency, a frustration emerged from a growing dissatisfaction with sluggish social progress even in the wake of increasing technological process. So, some people in America were benefiting during the decades running up to the hippie movement, but many weren't. This is a recipe for a social movement/revolution.
I would only add that the anti-war movement was incredibly significant, as it has already been said. Remember that there was a draft, a mandatory enlistment to fight in the war. The hippie movement raged against this idea of the government forcing young people to fight in a war they felt was totally unjustified. So, the movement was against the war which was American imperialism abroad, but also domestically (McCarthyism occurring in the 1950s).
The hippie movement gets a bad rap sometimes because, to some, it was an escape, a happy-go-lucky lifestyle. It was that for some, but many hippies were aligned with groups like the Black Panthers and the SDS (Students for a Democratic Society), militant groups who were very serious about instigating social reforms.
For many young people, joining the hippies was simply easier than working, being responsible and chaste--it was fun. They could smoke marijuana everyday and walk around the college campus as they dodged the draft into the Vietnam War wearing their blue glasses while mimicking the revolting group, spouting phrases, listening to Jim Morrison and the Doors or other "head" songs ad nauseum, etc. Indeed, there were many "hippies" who fit this profile and really did not have the ideology of the true Hippies.
The 1960s was a period in which more young people attended college than ever before. With closet Communist professors in the universities, these students were often introduced to the ideas of communal living, sharing the wealth, and revolting against the "Establishment." Rebelling against the conservativism of their parents who had endured the Great Depression was appealing to these pliable young adults, and with new phrases to use and drugs and sex available, the enticement was there. The Hippie Movement was the precusor of the Entitlement Programs; there just was no taxpayer money given away, yet.
The Hippie movement was the second generation protest against the "establishment" that followed the Beat Generation. The Beats were the generation that grew up during the World War II era and had to make sense of the rules and behaviors of the established political and wartime authorities and the political-industrial partnership. Examples of what this generation had to grow up in America with was food and other rationing, working mothers and soldier fathers, most of whom returned home with post-traumatic war syndrome though then it went by other, less psychological names.
The Beat Generation began the the protest against the attempt in the late 1940s and 1950s to establish a new order in a post-world war era. The Beats (beatniks) were a small set of intellectual poets, authors and artists who didn't have an impact that enfolded great numbers of people into their esoteric movement, but the next generation of youths, more of whom than ever in history were college educated (thanks to the GI school grants that opened colleges to others than the elite), were able to attune themselves to antiestablishment Beat protests against rigidity and cultural confinement, both of which defined and limited possibilities while at the same time, ironically, offering unprecedented opportunity. "Dropping out," "free love," "flower power," "tuning out and turning on," "good vibrations" and "living off the land" Hippie ideologies were fueled further by social and political factors from Leary's LSD to Vietnam to militant Black Panther civil rights protests.
I have heard it argued, from people who lived during that era, that the anti-war movement was actually only a small part of the overall hippie culture. The hippies were less about fighting the system and more about living outside of it; they didn't want to control or rule, but only to exist without being unduly judged or harmed by society. In that sense, the hippie movement would grow from a general opposition to authority; while many hippies marched and protested, many more simply dropped off the grid and ignored the larger issues in society at the time, preferring to focus on their personal development.
Another theory is that hippies/proper did not truly exist until after Robert A. Heinlein inadvertently created them in his novel Stranger in a Strange Land. The book was published in 1961, just before the full force of hippiedom descended on the U.S., and its 1963 reprint was taken as a sort of lifestyle bible by many in the culture.
The Hippie movement was a perfect storm of circumstances. The counterculture was a response to the mainstream culture, of course, but the movement would never have been some meaningful without the war protest aspect. It gave the movement a vision, and made it more than drugs and orgies.
Disenchantment with the American Dream was part of it. Kennedy's election promised prosperity.
However, that golden age never materialized. On the contrary, by the end of the 1960s it seemed that the nation was falling apart. (history.com)
People expected peace and prosperity, but what they got was war. Young people will often revolt against a world they do not feel ready to accept. All of these things contributed to the widespread Hippie Movement.
One other factor I'd cite in addition to the others was the Civil Rights movement and its many "spinoffs," if you will. While I wouldn't draw many connections between the so-called "Classical" Civil Rights Movement and the counterculture movement, the many later variants of civil rights, such as "black power," were very influential among counterculturalists. I think also--and here I'm being a little more cynical--that mass media played a large role as well, with the mass-marketing of music, clothing, art, and other aspects of the "hippie" lifestyle.
I agree with the reasons expressed in the above posts. There was a backlash against the Vietnam War and the military-industrial complex and the burgeoning consumer culture of the post-World War II years. Many youth (but not youth only) desired a different way of participating in society. They desired more freedom from what they perceived as the constraints on them from the 'establishment' society of their parents.
Indeed, many sought a return to living off the land and a simpler life. They wanted to experiment with a belief system that didn't always conform to the belief system of those who helped shaped their lives in their formative years (their families, their communities, the education system, the government).
Posts 2 and 3 make very good points that were the first things that I thought of when I considered the question. In addition, I think we should also look at the effect of media coverage of the war in Vietnam.
In World War II, there was very little opposition to American involvement in the war. The news media did not question our purpose or our methods. However, Vietnam became a completely different story. I don't think the "hippie" movement would have been nearly as powerful with the anti-war sentiment that opposed it, and this sentiment was fueled by the type of media coverage we saw on tv and in the papers every day. Young people have an instinct to rebel to at least some extent, and the pictures we saw from Vietnam strongly encouraged and anti-war feeling. Meanwhile, the parents of these teens were the people who sacrificed to help us win World War II. So there were two very different mindsets at work.
Anti-war and anti-Vietnam sentiment; a desire to live a freer life with fewer materialistic possessions; a move back to the earth where many small farms turned into small communes of young people; the urge to make a lifestyle change that reflected an alternative to parents' beliefs and the more rigid conservative beliefs of the era. Add drugs, music and sex to the mix, and the hippie lifestyle became quite seductive to many young adults who weren't quite ready to make commitments--especially toward employment and careers--for future goals.
One reason that we can give for the rise of the Hippie movement is the materialism and conformity of the 1950s. The people who had lived through World War II (and much of the Depression as well) really wanted to build comfortable lives for themselves. They had had enough of hardship and wanted material comforts. Their children grew up with more material goods than their parents had had, but they also felt that their parents cared only about material goods. They felt that their parents lacked any real feelings and humanity in their lives. Therefore, they rebelled. They felt like they were going to create a new culture that was less concerned with material goods and with conforming to society’s expectations.