CINCINNATI » Jim Obergefell says he "instantly pictured growing old" with John Arthur when they fell in love here in 1992. Just seven weeks after they began dating, Arthur gave Obergefell a ring set with diamonds – a sign that, in their hearts if not in law, they were married.

Two decades later, with Arthur dying of amyotrophic lateral sclerosis (Lou Gehrig’s disease), they did marry, aboard a medical charter jet on the tarmac of an airport in Maryland – a state where, unlike Ohio, gay people could wed. When Arthur, 48, died in October 2013, Ohio refused to list Obergefell as his spouse on the death certificate. Furious, Obergefell sued.

Now Obergefell, 48, a soft-spoken, bespectacled real estate agent who says he never intended life as an activist, is the lead plaintiff in a Supreme Court case that could topple Ohio’s ban and establish a national right to same-sex marriage. As the court prepares to hear arguments Tuesday, gay rights advocates around the country point to his case as evidence of discrimination.

But here in Cincinnati, where Mayor John Cranley calls Obergefell a "historic figure," his case has become the measure of something else entirely: how far the gay rights movement has come in one of the most traditionally conservative corners of the Midwest.

As recently as 2004 – the same year Ohio adopted its same-sex marriage ban – Cincinnati was the only city in the nation whose charter expressly barred ordinances related to gay rights; critics called it "the most anti-gay city in America." Today Cincinnati has its first openly gay city councilman, and leaders market the city as friendly to lesbians, gays, bisexuals and transgender people.

The city has a domestic partner registry and recently extended "transgender inclusive" health benefits, including hormone therapy and sex reassignment surgery, if a doctor deems it medically necessary, to city employees. Cincinnati is technically a defendant in the Obergefell suit, but its attorneys refuse to defend Ohio’s ban. The City Council recently presented a proclamation to Obergefell, naming April 28, the date of the Supreme Court arguments, John Arthur Day in Cincinnati.

"Having a reputation as an open, inclusive city is good for business, it’s good for economic growth, it’s good for quality of life," Cranley said in an interview. "It increases the happiness quotient."

It is an extraordinary turnaround in a city that was known for its moral conservatism, fueled in part by the influence of the Roman Catholic Church, and high-profile battles against abortion and pornography, as well as gay rights. R. Albert Mohler Jr., the president of the Southern Baptist Theological Seminary, who came here this month for a forum on same-sex marriage, said in an interview that Cincinnati had long stood as "a firewall" against the kind of moral degradation that, he argues, will come if gay people can wed.

"If this kind of moral change can happen in Cincinnati," he warned, "it can happen anywhere."

In some respects, the transformation in Cincinnati has simply mirrored that of the nation, as more gay people came out to their friends and family.

The city councilman who presented Obergefell with his proclamation, David Mann, a Democrat, infuriated gay constituents in the early 1990s when, as mayor, he introduced Gay Tolerance Day instead of Gay Pride Day. Then he learned he has a gay son.

"We are doing what we can," he said, "to convert Ohio into a state that recognizes same-sex marriage."

In 2013, Sen. Rob Portman of Ohio, who is from Cincinnati, became the first sitting Republican senator to publicly support same-sex marriage after discovering that he, too, has a son who is gay.

But given its history as an epicenter in the nation’s culture wars, Cincinnati also has a distinct story to tell.

Various forces have been at work in changing attitudes. Procter & Gamble, a prominent corporation whose headquarters are here, became concerned that an anti-gay reputation would hurt business. The openly gay councilman, Chris Seelbach, elected in 2011, pushed for changes. Urban revitalization brought young gay professionals downtown. And The Cincinnati Enquirer’s coverage of the Obergefell-Arthur wedding in 2013, and the December suicide of Leelah Alcorn, a transgender teenager, set off an emotional outpouring.

"For Cincinnati, the response was amazing," said The Enquirer’s editor, Carolyn K. Washburn, who grew up here, left 30 years ago and returned in 2011. Of the wedding, she said, "Everyone understood that it was historic and it was part of the news sweeping the nation, and that it was an incredible love story."

Cincinnati’s place in the culture wars dates at least to the 1960s, when a local obstetrician, Dr. John C. Willke, helped found the anti-abortion movement. In 1977, Larry Flynt, the publisher of Hustler magazine, was convicted here on obscenity charges. In 1990, the Contemporary Arts Center came under attack for exhibiting the photographs of Robert Mapplethorpe, a gay artist known for his erotic nudes.

In 1992, Cincinnati, under Democratic leadership, adopted a law banning discrimination in housing and employment based on sexual orientation. Phil Burress, a former union organizer who runs the advocacy group Citizens for Community Values, decided to put a stop to it. From his office in the Cincinnati suburb of Sharonville, Burress, 73, has spent decades working to stamp out pornography, strip clubs and what he calls "the homosexual agenda."

In 1993, he mobilized a successful voter initiative to amend the city charter that stated, "No special class status may be granted based upon sexual orientation, conduct or relationships." It passed with 62 percent of the vote. Known as Article 12, the amendment barred Cincinnati from adopting any kind of law – such as hate crimes legislation or anti-discrimination bills – aimed explicitly at protecting gay people.

In 1996, the Supreme Court overturned a similar Colorado law, but the courts allowed Article 12 to stand. Seelbach, the councilman, says the amendment "was devastating for our city," driving away gay residents, "top talent" and $40 million in convention business.

In 2002, gay rights advocates including Seelbach, now 35, began planning a repeal campaign. The effort received a major boost when Procter & Gamble donated a full-time employee to lead it.

"P&G is not just a big corporation," said Dan Hurley, a local historian. "They are the corporate institution in Cincinnati, period."

In 2004, Cincinnati voters repealed Article 12, by 54 percent to 46 percent. It was a bright spot in an otherwise bleak year for gay rights; that year, 13 states including Ohio banned same-sex marriage.

Burress, who led the effort for Ohio’s same-sex marriage ban, insists the repeal was a fluke. He says voters were confused, and attributes the ensuing changes in Cincinnati to a "mass exodus" of conservatives who left for the suburbs.

"The city is going belly up as far as values," he said. "The left has taken over."

Changing demographics have indeed led to a shift in attitudes. Cincinnati’s Over-the-Rhine neighborhood, a historic district known for its Italianate architecture, was once blighted and dangerous. Now it is home to boutiques, restaurants and many gay residents, including Obergefell and Ryan Messer, a civic leader and regional manager for Johnson & Johnson who was Seelbach’s first donor.

"Our city is hugely changed," said Angela Vance, who two years ago became the Cincinnati Police Department’s first "LGBT liaison." She winced recalling how two decades ago colleagues referred to her as a "dyke." Now she works from an office decorated with rainbow-colored flags and trinkets – just down the hall from the chief – investigating harassment complaints and conducting sensitivity trainings.

"I’m proud now," Vance said, "and I can’t say that I have always been, living in Cincinnati."

Today, national gay rights advocates hold up Cincinnati as a model. Last fall, officials of the Human Rights Campaign traveled here to unveil the results of their Municipal Equality Index, which grades cities based on their policies. Of 353 cities, 38 – including, for the first time, Cincinnati – received a perfect score of 100.

"Pigs have not yet flown," The Enquirer wrote at the time, "but really, what is left to happen?"

On a rainy night recently, more than 400 people packed into a downtown ballroom, the Phoenix, for the second in a series of storytelling events sponsored by The Enquirer. In light of the coming Supreme Court arguments, the theme was "finding love and acceptance" in the city’s gay community.

A transgender musician invoked "the spirit of Cincinnati" and said she could "finally live my truth." A drag queen said he hoped to make life "a little easier to live every day." Messer, the civic leader, announced that he and his husband were about to "have another baby." Vance made an impromptu appearance.

But none got quite as warm a reception as Obergefell, who received a standing ovation before saying a word. The crowd listened as he recounted a tale most already knew: of falling in love with Arthur; of a disease that "upended our world"; and of his legal quest to "stand up for my husband, to love and protect him."

But this time he added a postscript, about a class in urban planning that Arthur took at the University of Cincinnati in the 1980s.

"Because of that class," Obergefell told the crowd, "John said he would always live within the city limits of Cincinnati. And I’ve got to tell you, he made the right decision."

Sheryl Gay Stolberg, New York Times

© 2015 The New York Times Company