According to Michael Williams, much better known as “Sister Roma,” the story of the Sisters of Perpetual Indulgence began in San Francisco on Easter Day of 1979. Back then, just a year before the city’s gay community was struck by the AIDS epidemic, four friends found themselves fed up with what Roma called the “Castro clone look.”

“Gay men in San Francisco in the 70s all presented very masculine, leather jackets, moustaches, sort of like the Marlboro Man, you know?” Roma told NBC News. “So they were very fed up with that, and they thought, ‘Let’s put on these nun’s habits and sort of go out and screw with people and see what happens.’”

As they strolled from the Castro to the city’s gay beach, Roma said, “everywhere they went the reaction was just insane — people had never seen anything like men, most of them with facial hair, in nun’s habits.” They realized they were onto something, so they came up with a name for their group: The Sisters of Perpetual Indulgence.

Now four decades later, The Sisters of Perpetual Indulgence were clearly ahead of their time, and many of their campy “dragtivism” tactics have inspired others, Roma said. “Little did they know it, but these four queers who went out in these nuns habits actually changed the world,” she said.

“One of the original sisters was Bobbi Campbell, who was Sister Florence Nightmare, who was a registered nurse,” Roma said.

Campbell became well known across America as the self-designated “AIDS poster boy,” a role he took on in an effort to destigmatize the disease.

“The sisters took a very pragmatic, responsible attitude towards the virus, and said, ‘We need to protect the community,’” Roma said. “So the sisters produced a safer sex pamphlet called Play Fair that we still produce today, that was the world’s first-ever safer sex pamphlet.”

In the early 1980s, The Sisters of Perpetual Indulgence hosted some of the world’s first fundraisers for AIDS victims, many of whom faced financial ruin as the then-unknown pathogen ravaged their bodies. “The sisters were at the forefront of the fight against HIV/AIDS before anyone knew what the disease was,” Roma said.

Members of the Sisters of Perpetual Indulgence, San Francisco's beloved sect of cross-dressing nuns, attend The Hunky Jesus Competition event at Dolores Park in San Francisco on April 1, 2013. John S Lander / LightRocket via Getty Images file

At each anniversary every 10 years, the sisters have had a different focus. In 1989, Roma launched the "stop the violence” campaign, which addressed an uptick of homophobic hate crimes in San Francisco at that time.

“In 1989, queer people were still really fighting for equality and just desiring to be recognized as equal people in the world,” Roma said. “So it was a very basic fight, and we were also crippled with HIV and AIDS, which many people saw as a disease that was killing all the right people.” That year, The Sisters of Perpetual Indulgence also became an official nonprofit organization.

For their 20th anniversary in 1999, the Sisters closed Castro Street for a massive celebration. “That seemed like a no-brainer to us, but apparently it was quite a major issue for a lot of people in San Francisco, who still at the time ... thought that we were very sacrilegious,” Roma said. But support from local politicians got them through the day, and they hosted their street fair, where the Sisters emceed a “hunky Jesus” competition that continues to this day.

Members of the Sisters of Perpetual Indulgence, San Francisco's beloved sect of cross-dressing nuns, attend The Hunky Jesus Competition event at Dolores Park in San Francisco on April 1, 2013. John S Lander / LightRocket via Getty Images file

Because of publicity generated by the opposition, “it was one of the largest celebrations that we had, probably ever in our history,” with around 20,000 to 30,000 people filling Castro street, Roma said.

For their 30th anniversary, the sisters focused on the political issues animating the LGBTQ community at that time.

“We started to talk about gays in the military, and same-sex marriage, and adopting children,” Roma said. “So the sisters again picked up the bullhorns and buckets and collected money and raised awareness for all of these important issues.”

For this weekend’s 40th anniversary in San Francisco’s Mission Dolores Park, the Sisters will turn their focus to a new set of issues, Roma said, like transgender and migrant rights, as well as anti-gay laws like the one recently passed in Brunei. “But we are also thinking about the jeopardy of our own civil rights and our own safety in this country as the pendulum swings back to the right,” Roma said.

When considering a protest against Mayor Pete Buttigieg earlier this week, in which protesters donned religious garb for dramatic effect, Sister Roma acknowledged that the troupe’s performative style of activism may have had an impact outside the LGBTQ community.

“Let’s face it, religion is campy. It’s pomp. it’s circumstance, it’s burning purses that smell like incense, it's candles and stained glass windows and robes and brocade,” she said. “Is there anything gayer than religion, really?”

The Sisters of Perpetual Indulgence will celebrate their 40th anniversary this Easter Sunday in San Francisco’s Mission Dolores Park from 12 p.m. to 4 p.m.

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