In 1970, Marjorie Jones and Tracy Knight - a same-sex couple in the US state of Kentucky - decided they wanted to get married.
But when they entered the county clerk's office in Louisville to get a marriage license, the clerks "went into shock and disbelief", recalled Lynn Pfuhl, a founder of an early gay rights group in Louisville, who accompanied the two women to the office.
"And then when they [the clerks] got the idea that we were serious, their faces more or less froze into a look of hatred."
The women, of course, weren't granted a marriage license. Claiming that their constitutional rights had been violated, they sued. In one of the first court cases in the United States to address the issue of gay marriage, an appeals court rejected their argument, finding that "the relationship proposed does not authorise the issuance of a marriage license, because what they propose is not a marriage".
This February, more than 40 years since Jones and Knight went to court, a federal district court judge overturned part of Kentucky's ban on gay marriage.
That was just one episode in a slew of victories this year for same-sex marriage proponents. On Monday, a judge in Oregon struck down the state's voter-approved ban on same-sex marriage as unconstitutional.
Earlier this year, federal district judges handed down rulings in a number of other states - including deeply conservative places like Arkansas, Idaho, Oklahoma and Texas - doing away with bans on same-sex marriage. Those rulings have been appealed, and now, it seems to be only a matter of time before the Supreme Court will hear a case on whether states' same-sex marriage bans are constitutional.
|US state sued for same-sex marriage U-turn
These victories have come as a surprise to Pfuhl, who said she "never thought it would happen" during her activism in the 1970s.
But behind the legal wrangling, there's been a rapid shift in how Americans view same-sex marriage. In the 1970s, it was unthinkable to all but a small number of people. In 1996, about one-quarter of Americans supported gay marriage. Now, more than half say they do. With the exception of marijuana legalisation, almost no other issue in the past decade has seen such quickly changing fortunes.
Could Americans' change of heart on same-sex marriage be part of a broader libertarian trend? Conservative columnist Michael Barone posited a connection between rising support for gay marriage and legalising marijuana, and a simultaneous drop in support for gun control measures. "In all three cases," Barone wrote, "Americans have been moving toward greater liberty for the individual".
According to a 2013 report by the Pew Research Center, about one in five of those who changed their minds on gay marriage cited opposition to government involvement as the reason.
But the trend is not clear-cut: Patrick Egan, a political scientist at New York University, noted that public opinion on other social issues, such as abortion, has barely budged over the same timeframe. And traditionally libertarian demands like lower taxes do not seem to have become more popular over the past decade.
The Pew report found that an overwhelming majority - 70 percent - of Americans born after 1980 back gay marriage. Just 31 percent of people born before the end of World War II feel the same way.
Support for same-sex marriage, then, is surging as older generations die off and are replaced by younger Americans - who, unlike their elders, have grown up at a time when gay marriage has always been an actively debated issue.
Patrick Egan, a political scientist at New York University, speculates that younger Americans are much more supportive of same-sex marriage because of a "cultural shift in how gay people are portrayed … We see a lot more openly gay people, and their portrayal is just much more positive than it was 10 or 20 years ago". Egan also noted that younger Americans are much less likely than older generations to be involved in organised religion - which correlates with opposition to gay marriage.
Echoing Egan's assessment, Brian Silva, the executive director of Marriage Equality USA, said opinion is shifting because "our personal stories and how our lives are affected really have an oversize impact on changing people’s minds".
A significant number of older people have also changed their minds on gay marriage. Why? One argument goes that the issue has been framed in a way that makes it palatable to middle-of-the-road Americans. Andrew Sullivan's seminal 1989 article, "Here Comes The Groom", was one of the first to make this case: "Gay marriage … says for the first time that gay relationships are not better or worse than straight relationships, and that the same is expected of them. And it's clear and dignified."
Pfuhl concurred, arguing that emphasising the right to marry "affirmed major social institutions instead of wanting to question them, tear them down and build something new".
But Sullivan's focus on marriage was hotly debated within the LGBT community at the time - and still is to an extent today - with some activists viewing the fight for matrimony either as a sideshow to more important issues or as a sell-out to heterosexual norms.
Meanwhile, as the idea of gay marriage has become increasingly mainstream in the US, opponents speak of being sidelined from the public discourse, hampering their ability to win over minds.
"The media has closed ranks on the pro-family movement," said Brian Camenker, who leads Mass Resistance, a Massachusetts-based group that opposes gay marriage. "They've basically decided that the case is closed, and that anybody who differs on the issue at all is an extremist."
Is the battle over?
Gay marriage is still only legal in 18 of the US' 50 states. But the momentum on the pro-gay marriage side is such that some opponents have already expressed defeat. "A major, decisive battle in the culture war is over. The other side won. Soon their efforts will amount to little more than bouncing the rubble," wrote The American Conservative's Rod Dreher.
We see a lot more openly gay people, and their portrayal is just much more positive than it was 10 or 20 years ago.
One sign of the shifting tides: Whereas the amount of money spent by supporters and opponents of Proposition 8 was about even, in 2012 supporters of gay marriage initiatives outspent their rivals nearly three-to-one. Many of America's super-rich - especially those in the tech industry - have been generous donors supporting same-sex marriage. Meanwhile, once-big funders of gay marriage bans like the Mormon Church appear to have become less vocal on the issue.
"You simply can't fight this thing when you're being out-funded like 100-1, and every major company gives enormous amounts of money to the other side," said Camenker.
In describing the Sexual Revolution of the 1960s, British poet Philip Larkin described a moment when, suddenly, "all at once the quarrel sank", and "everyone felt the same".
It'd be an exaggeration to say that's also the case with gay marriage in the 2010s. But Pfuhl, the Kentucky activist who was also involved in the civil rights movement, speculates that "just as nobody much thinks about interracial marriage now, maybe 20 years from now nobody will think about same-sex marriage".
If the polling numbers continue on the same trajectory, she may well be right.
Follow Sam Bollier on Twitter: @SamBollier