On Dec. 31, 1966, a dozen plainclothes policemen observed the New Year's festivities inside the Black Cat, a gay bar in Los Angeles' Silver Lake neighborhood. At the stroke of midnight, as revelers celebrated with "Auld Lang Syne" and the traditional New Year's kiss, uniformed cops burst into the bar, billy clubs swinging. For many of the bar's customers, 1967 began with a blow to the head.

Sixteen patrons were arrested inside the Black Cat, and police chased two more men into New Faces, another gay bar nearby. There, the cops struck the female owner and beat three employees who came to her defense. According to Lillian Faderman and Stuart Timmons'book Gay L.A., one of the bartenders suffered a ruptured spleen; when he came to at County General Hospital, he was charged with assaulting an officer. The New Year kisses led to six men being charged with lewd conduct. All of them were found guilty.

The gay community was outraged by this police harassment. Activists organized protests and distributed leaflets outside the Black Cat for weeks after the raid. But thanks to Los Angeles' sprawling geography, few passers-by witnessed the incident or noticed the protests, and the episode received little media attention. It would be two and a half more years before a similar incident, at a bar on the opposite coast, would change the gay rights movement forever.

It's no accident that this movement was born in a bar. In the 1960s, more and more gay men and lesbians were frequenting such establishments, even though they were often targeted by law enforcement for raids and crackdowns. In the tumult of the civil rights movement, a confrontation on this turf was bound to happen. And yet there were many incidents like the one at the Black Cat that failed to ignite widespread anger and protest. It took a special combination of circumstances to spark the movement, circumstances that came together at the Stonewall Inn almost by accident—and would be hard to re-create afterward. The Stonewall Inn holds such an iconic place in gay history (and, as we saw when joyful New Yorkers gathered there to celebrate the passage of marriage equality legislation, it remains iconic today) that it can be hard to remember how unusual the incident was. What was it about the night of June 28, 1969, that was different than all the nights that came before it—and all the nights that have followed?

In 1969, the Stonewall Inn at 51-53 Christopher Street was well-attended but not well-liked. Writer Vito Russo described it as "a regular hell hole. The pits. It was also one of the hottest dance bars in Greenwich Village. It was a bar for people who were too young, too poor or just too much to get in anywhere else. … A place everyone loved to hate. Seedy, loud, obvious and heaven." People went there because it was relatively large, and because it was one of the few gay places in the Village that allowed dancing. But it had little else to recommend it. There were no fire exits, drinks were watered down yet expensive, and the hygiene standards were appalling. There was no plumbing behind the bar; dirty glasses were simply dipped into a rubber tub filled with filthy water that sat there all night. (In 1968, this practice was suspected to be the cause of an outbreak of hepatitis.) The New York Hymnal described the Stonewall as having a "filthy john" and "high prices" and declared it "the tackiest joint in town."

Like most gay bars in New York, and elsewhere on the East Coast, the Stonewall was run by the Mafia. The Mob sought out establishments that operated in a twilight world, where they could water down the liquor, sell untaxed cigarettes, and run prostitution, blackmail, and other illegal rackets. They kept the bars in the twilight by paying off the local cops. (In his book Stonewall, Martin Duberman puts the Sixth Precinct's weekly take from the Stonewall Inn at $2,000 cash.) Still, police raids on gay bars were common. The cops might raid a bar because they wanted a bigger payoff, because a bar was flouting the law too brazenly, or, in a mayoral election year like 1969, because the incumbent administration craved newspaper headlines about cleanups and clampdowns.

The Stonewall Inn was raided just days before the most famous night in gay history. According to David Carter's Stonewall: The Riots That Sparked the Gay Revolution, Seymour Pine, a deputy inspector with the NYPD, was determined to close the place down because its efforts to pass as a "bottle bar"—a private club where members could leave their own bottles of liquor from which only they could be served—were insultingly desultory. On Tuesday, June 24, Pine arrested bar personnel and confiscated liquor, but as he was leaving, the bar's owners had bragged, "We'll be open again tomorrow." Carter suggests that Pine was "stung" by this defiance, in part because he knew it was true. The bar reopened on Wednesday. So Pine came back in the early hours of Saturday.

The police lost control of the June 28 raid soon after it began, though not for lack of planning. Pine obtained a search warrant, invited representatives of relevant city and federal agencies to ride along on the raid, and installed undercover police officers at the bar. Around 1:20 on Saturday morning, Pine and his men stormed in. They immediately faced resistance. Pine decided he had to arrest the uncooperative patrons for disorderly conduct, though he was still determined to take a careful inventory of all the alcohol on the premises to bolster his challenge to its legal status as a bottle bar. The rebellious patrons were held, along with anyone who failed to show ID, but the seizure and tagging of the alcohol took so long that the prisoners became restive.

The scene did not go unnoticed in the neighborhood: It was prime bar-hopping time, and the Stonewall was located at the center of gay Greenwich Village. A crowd had gathered outside the tavern by the time the police were ready to load up their wagons with contraband alcohol, Stonewall employees, and unhappy bar goers. When the cops started to manhandle their unruly prisoners, the onlookers became enraged, throwing coins, stones, and bottles at the officers. The police, a few prisoners, and a writer from the Village Voice who had noticed the fracas from his nearby office, were forced to retreat into the bar, which the mob then tried to set on fire. The cops were eventually rescued with the intervention of the fire department and the riot squad, which dispersed the crowd. But low-level protests lasted for four more days, flaring up for a final time on Wednesday, when the Voice published an inflammatory account of the uprising. Why did the gays of Christopher Street suddenly fight back after decades of persecution? Witness Morty Manford likened the melee to "a slight lancing of the festering wound of anger at this kind of unfair harassment and prejudice." He said, "We had just been kicked and punched around symbolically by the police. They weren't doing this at heterosexual bars. And it's not my fault that the local bar is run by organized crime and is taking payoffs and doesn't have a liquor license."

But Stonewall could easily have remained as obscure as earlier clashes like the one at the Black Cat were it not for a coincidence of time and place. In May 1959, a skirmish broke out around Cooper's Doughnuts, a shabby all-night Los Angeles coffee shop frequented by hustlers and their customers, when gays threw coffee cups and paper plates at police officers rather than submit to arbitrary arrests. This "was perhaps the first homosexual uprising in the world," according to Gay L.A. (If the protesters had not included writer John Rechy, the incident would almost certainly have been forgotten.) Similarly, in the summer of 1966, transvestite patrons of Compton's Cafeteria in San Francisco's Tenderloin district fought with cops who were trying to detain them. Again, the incident failed to generate attention.

But by the summer of 1969, gays were more willing than ever to challenge authority, thanks to the influence of the civil rights, feminist, and anti-war movements. The Stonewall raid also occurred on the first hot weekend of the summer, at the biggest club in the area, and in a pedestrian-friendly neighborhood that had recently become home to a growing number of homeless gay youths who had no property, jobs, or family ties at risk if they faced off against the cops. Two writers from the Village Voice, at that time America's pre-eminent alternative weekly, were among the hundreds of New Yorkers who stumbled upon the riots, so the story spread far beyond the immediate vicinity of the bar.

"Homophile organizations," the early term for gay-rights groups, had been springing up around the country, and although the events at Compton's and the Black Cat were not common knowledge, word had reached activists in New York's gay community. In the months following Stonewall these activists were able to transform the protests into a political cause, leading to the creation of the Gay Liberation Front and the Gay Activists Alliance, groups dedicated to the struggle for gay civil rights. Following the raid, activist Craig Rodwell advocated tirelessly to establish an annual reminder of the Stonewall uprising. Those early Christopher Street Liberation Day commemorations evolved into the Gay Pride marches of today.

Why were so many of the gay liberation movement's early battles fought in bars and restaurants? That was where gay men and lesbians socialized in groups—and where they came into conflict with the legal establishment. The bars, meanwhile, wanted raids to end—for the sake of their bottom lines. In 1964, a Bay Area gay-rights organization known as the Society for Individual Rights, whose members were predominantly bar goers, conducted voter registration drives in local taverns and published a wallet-sized legal guide called the "Pocket Lawyer" to advise patrons of their rights if they were abused by the police. In San Francisco in the early 1960s, gay-bar owners had come together to form the Tavern Guild, an organization that coordinated efforts to resist capricious actions by California's Alcohol Bureau of Control and provided assistance to anyone arrested in or near a gay bar. For the moment, the nascent gay rights movement had found a natural home in gay bars.

The gay bar as a locus of political organizing and resistance was short-lived, however. Once bar patrons were no longer being harassed, they were less likely to become active in the movement or to want a night of drinking to turn into a sit-in. As historian John D'Emilio observed in his book Sexual Politics, Sexual Communities, in San Francisco, "the success of the movement in bringing an end to the harassment of bars took the edge off the anger that led to SIR's founding."* When bars experienced less harassment, they no longer had a reason to be involved in the movement, and as far as patrons were concerned San Francisco's "flourishing bar culture made militancy less urgent, since the quality of their personal life had improved." Something similar happened in New York. The new gay-rights groups had learned how to draw attention to their cause, organizing "zaps"—splashy, media-friendly protests—whenever they identified homophobic behavior on the part of politicians, police, or the press. Politicians, whose attitudes could be swayed by a well-publicized demonstration, received the bulk of the groups' attention.

Gay bars didn't miraculously turn into utopian paradises on June 29, 1969, of course. Mafia control and police payoffs continued for some time. And when there was trouble at a bar, the new gay-rights groups made the most of the situation. In March 1970, for example, after a police raid on the Snake Pit, a (non-Mafia) Village gay bar, a terrified young Argentine jumped out of a second-floor window and impaled himself on a 14-inch spike while attempting to escape from police custody. The GAA immediately organized a protest march and a letter-writing campaign to draw attention to the police's inhuman treatment of detainees. The movement was now holding the authorities accountable for their behavior.

But in the years that followed, many bars disregarded politics and concentrated on making money. In 1977, the owner of the sole lesbian bar in Portland, Ore., told feminist magazine Pearl Diver, "I do not want this place turned into a political battleground. It alienates people. This is not a political place. This is a bar, a place where women should come to drink, and dance, to meet other women and have a good time." An October 1982 article in New York's feminist newspaper Womanews, reporting on the imminent closure of longtime Greenwich Village lesbian bar the Duchess, revealed the anger political activists felt at the bar: "Of the millions of dollars [the Duchess] has drained from the community on overpriced drinks and cover charges, it has consistently refused to give back even a dime to the larger lesbian community. It has refused to hold benefits, take out ads in feminist newspapers, or even allow them to be sold there, or in any way be responsive to the wishes of the lesbian community." The movement had been born in a bar, but it was no longer welcome.

It never really came back. When the AIDS crisis developed in the 1980s, bars distributed safe-sex information and free condoms, and they are still an important fundraising venue for AIDS service organizations and Pride committees. But they remained essentially apolitical institutions. Today, gay bars routinely make local bar rags and gay newspapers available, but that tends to be the extent of their engagement. It also became less vital to organize in bars as more gays and lesbians came out and the bar lost its central role in gay life.

Urvashi Vaid, the former head of the National Gay and Lesbian Task Force, described the failure of LGBT political groups to connect with gay bars as "a huge missed opportunity." She told me: "We never figured out how to organize successfully through the bars. You see tables—information, literature, those kinds of strategies. You don't see the bar owner or the party promoter sharing the bar [mailing] list with the local political organization." Today, gay political groups largely ignore the hundreds of thousands of Americans who spend Saturday night in their local gay bar.

The Stonewall Inn survived for only a few months after the June 28, 1969, raid. The building housed restaurants and shops until 1990, when the space was taken over, once again, by a gay bar. The current space is dreary and uninviting, though it seems to do decent business. At the Stonewall, anyway, politics, or at least a patina of politics, is good for business: The walls are decorated with iconic photographs from the riots (astonishingly, just one photo exists of the first night's protests, and only a handful more were taken over the course of the weekend) and from early Pride celebrations, though you won't be surprised to hear that there's no reference to Mafia exploitation or police payoffs. It's a working bar, not a museum, even if many of the customers have cameras hanging around their necks. There's just enough history on the wall to give them something to point and click at, and maybe an excuse to buy a cocktail or two.

Still, Stonewall is more than just a before and after marker, more than an event in the gay history books. It's a real place with a real appeal. On the night of June 24, 2011, a throng of first nervous and then jubilant customers gathered at the Stonewall to follow the New York State Senate's vote on same-sex marriage. It was Pride weekend, a drag parade was heading from Tompkins Square Park in the East Village to the Stonewall, and the neighborhood was already packed with revelers. As the senators announced their votes, and customers struggled to keep track, it seemed that a crowded, noisy bar wasn't the ideal location to monitor Senate business. But when the final tally was announced, and people realized that in 30 days, they, too, would finally have the right to marry, the Stonewall seemed the perfect place to be. A loudspeaker pumped gay anthems into Sheridan Square—Madonna's "Holiday," George Michael's "Faith"—while couples planned weddings, sought out husbands-to-be (one guy yelled: "I'm getting married! Now I just need a boyfriend"), and cheered on command whenever TV lights illuminated the street. Politics had returned to the bar for one night at least, and it was a glorious, festive celebration.

Correction, June 28, 2011: This article originally misstated the title of John D'Emilio's book Sexual Politics, Sexual Communities. (Return to corrected sentence.)

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