The black-tie dinner at the National Gallery of Art was a dazzling affair. To celebrate the September reopening of the East Wing after a three-year renovation, the gallery invited 450 art donors, collectors, artists and other dignitaries to view the collection of modern art and then enjoy champagne, caviar, bison and hand-sculpted chocolate terrariums presented under individual glass domes.

David Rubenstein, one of the gallery’s five trustees, was sitting at his table when a guest came over to greet him. “David! How are you?” the man exclaimed, then turned to the person seated to Rubenstein’s right. “Hi! Who are you? What’s your name?”

“John Roberts.”

“And what do you do?” the man continued, clueless.

Rubenstein hastily explained that his dinner partner was the chief justice of the United States. Roberts was unflappable, the man embarrassed. But when another guest approached Rubenstein for a selfie, the billionaire gently suggested that one with Roberts would be more impressive.

The idea that the chief justice was not instantly recognizable, even in a room full of VIPs, would have been shocking just 10 years ago. But Washington’s social landscape has changed dramatically in the past decade, driven by bitterly partisan politics and a booming private sector.

Long before Donald Trump was elected president, politicians and administration officials who had traditionally topped Washington’s A-list were opting out of the social scene, replaced by philanthropists and CEOs willing and eager to make their mark on the nation’s capital and its institutions. The handful of federal officials at the East Wing dinner was eclipsed by philanthropists like Rubenstein, Roger and Vicki Sant, Calvin and Jane Cafritz, Adrienne Arsht, Mitch and Emily Rales, and Connie Milstein, all billionaires or millionaires.

In this respect, Washington — once a one-industry town where politics dominated every aspect of life — is becoming more like other American cities, where business titans like Carnegie, Mellon and Rockefeller shaped the cultural and social fabric. A city where big money and big ambition outshine titles or tradition.

Former first lady Laura Bush and George W. Bush at the annual Wolf Trap Ball in Vienna, Va. Laura Bush was a special guest at the September event. (Deb Lindsey /For The Washington Post)

On a Friday night in September, the Wolf Trap Ball kicked off the fall social season — a fancy catchall phrase for the parade of receptions, galas, dinners, book parties and other ways of raising money in Washington that starts after Labor Day and ends just before holiday parties begin.

Wolf Trap had a very special guest: former first lady Laura Bush, who came to celebrate the 100th anniversary of the National Park Service and brought her husband along. The Bushes, brimming with good cheer and bad jokes, charmed the 800 people on the Filene Center stage, including Supreme Court Justice Ruth Bader Ginsburg, Interior Secretary Sally Jewell and the British and Irish ambassadors.

But the key players were the money men who filled the gala with present and future donors: Wolf Trap Chairman of the Board Dan D’Aniello, the billionaire co-founder of the Carlyle Group investment firm, as well as Fred Humphries and Tim Keating, who co-chaired the ball with their wives.

Humphries, vice president of government affairs at Microsoft, and Keating, vice president of government operations at Boeing, read out a list of the evening’s top sponsors. “I’m proud to be co-chair of the Wolf Trap Ball,” Keating told the crowd. “This is the third time I’ve had this honor, and, I swear to God, it is the last time.”

The two men announced that the party had raised a record $1.5 million for the Wolf Trap Foundation’s educational programs. Wait, not quite — they were actually $8,000 short. “Every pocket in this room has been picked at least once,” joked Keating, who then said that he and his wife would make up the difference and that Boeing would match it.

There was laughter and applause, and then Keating asked everyone to fill out the donation cards at each table and give just a little bit more.

Guests sit down to dinner at a gala before the National Symphony Orchestra’s season opener at the Kennedy Center in Washington. (Deb Lindsey /For The Washington Post)

There was a time, not that many decades ago, when Washington’s social elite would never have deigned to mingle with corporate executives, no matter how wealthy or well-connected. Washington was insular, WASP-y and, if we’re being frank, full of snobs.

The storied Georgetown set arrived in two waves — the first with FDR, the second with JFK — and had family fortunes, East Coast pedigrees and ties to the White House. There were very few large balls; hostesses entertained at home, seated guests according to a strict hierarchy of rank and title, and rarely mingled outside their tight social circles.

Everything shifted in the 1990s. Politicians and their families, who used to live in Washington and socialize together, started commuting to and from their districts every week to avoid being perceived as inside-the-Beltway sellouts. Ethics scandals scared some politicians away from parties; others proclaimed that they’d been sent to Washington to tear the place down, not sip champagne with the establishment elites. Those legendary dinner parties, where politicians from both sides of the aisle debated the future of the world, died a quick and brutal death.

At the same time, the local business community began to grow: tech companies in Virginia, biotech in Maryland, private equity firms and hedge funds in the District. Suddenly, there was a lot of money in Washington that wasn’t dependent on the federal government, and a new wave of wealthy businessmen with deep pockets and high profiles, like the late multimillionaires Joe Robert or Jim Kimsey, best friends who used to publicly challenge each other to write the biggest check for their favorite charities.

“Old money, high-ranking government officials and the top ambassadors — that was the A-list” of old, says journalist Kevin Chaffee, who has covered Washington society for almost 40 years. “Now it’s new money who like to give it away: media, and a certain smattering of the old categories, but they’re less important.”

Who are the social leaders of today? Chaffee, now senior editor of Washington Life Magazine, has a working definition: “If they walk into the room and everybody’s heads turn, then they’re on the A-list.”

Any president and first lady are obviously top draws, and Washington will soon face the unprecedented spectacle of having both the former and current president in residence. It’s always a coup to get high-profile political and media personalities such as Secretary of State John Kerry, Democratic leader Nancy Pelosi, CNN’s Wolf Blitzer or any of the Supreme Court justices.

But the classic path to achieving social status is paved with gold: (1) Make or inherit money. (2) Start giving back. (3) Make a name as a philanthropist. For some people it’s a byproduct of a successful career; for others, the goal.

Most of today’s A-list — a racially diverse group of wealthy Democrats and Republicans, corporate heads and entrepreneurs — aren’t people whom most would recognize on the street: Atlantic Media owner David Bradley and his wife, Katherine; foundation head Catherine Reynolds and her husband, Wayne; BET chief executive Debra Lee; candy heiress Jackie Mars; superlawyer and Clinton confidant Vernon Jordan and his wife, Ann; Wizards and Capitals co-owner Raul Fernandez and his wife, Jean-Marie; former White House social secretary Lea Berman and her husband, Wayne; biotech entrepreneur Sachiko Kuno; Republican hostess Buffy Cafritz; AOL co-founder Steve Case and his wife, Jean; Washington Kastles owner Mark Ein and his wife, Sally; and dozens more. They’re known and respected in corporate and philanthropic circles, but not celebrities in the conventional sense of the word. Their social status comes from leveraging their names, raising money and supporting a number of local charities.

It’s easy to sneer at new money, says Chaffee, but the fact is, they give and give big. This new social order — less snobby, more generous — is arguably better for the city and for everyone who lives here.

“There’s nothing more democratic than having a lot of money,” he says.

Philanthropist David Rubenstein at the gala celebrating the reopening of the East Wing at the National Gallery of Art in Washington. (Deb Lindsey /For The Washington Post)

On the last weekend of September, David Rubenstein attended seven events.

On Friday night, he kicked off the Library of Congress Literacy Awards, then raced to the Kennedy Center for a concert celebrating the new National Museum of African American History and Culture. (His car got caught in traffic behind President Obama’s motorcade, so Rubenstein sprinted two blocks on foot and was blocked by the Secret Service until the president spotted him and waved him through.)

On Saturday, he attended the museum’s morning dedication (his gift of $10 million was one of the largest) and its gala dinner that night; in between, he squeezed in interviews with Shonda Rhimes, Bob Woodward and Diane Rehm at the National Book Festival.

On Sunday, he dropped by the National Archives Foundation gala with “Hamilton” creator Lin-Manuel Miranda, then headed to the Kennedy Center, where, as chairman, he opened the National Symphony Orchestra season.

“‘I’m not doing anything I don’t enjoy,” he explains in an interview at his Carlyle Group office. “Giving back to the country is fun. I came from very modest circumstances. I now find myself in Washington with a fair amount of money and the access to people that I’d only dreamed about when I was growing up in Baltimore.”

As a young White House staffer in the Carter administration, he was just another face in the crowd of bright young things. Then he spent 20 years building Carlyle and made his fortune, which now hovers at around $2.5 billion. After giving away hundreds of millions and with plans to give away another billion, he’s having his version of fun. He travels 200 days a year for work; when he’s in Washington, he’s at an event every night. He multitasks his life, inviting friends to join him at galas and other parties.

Rubenstein waves off any suggestion that he’s at the top of Washington’s A-list. Naturally shy, he doesn’t think of himself as a particularly social person, doesn’t drink and doesn’t care much for small talk and backslapping. His idea of a really good time is a serious conversation that helps him understand what makes people tick. His social ambitions boil down to this: “What is life all about but getting to meet interesting people who have done interesting things?”

His problem, he explains, is that he’s 67 years old. Classmates from law school are at the end of their careers, or dead. He’s rich, healthy and lucky. And he knows it.

“I want to get things done between now and when my brain falls apart or my body collapses,” he says. “I call what I’m doing ‘sprinting to the finish line.’ ”

That’s good news for the Kennedy Center: Rubenstein agreed to become chairman in 2010, donating millions and introducing the national arts center to dozens of his wealthy friends — D’Aniello, one of his co-founders at the Carlyle Group, underwrites Italian operas at the Washington National Opera.

The bad news is that no one person, no matter how generous, can sustain an entire institution. The challenge for everyone is finding that next generation of philanthropists.

“Everybody can name the top 30 wealthiest people in Washington,” says Marie Mattson, vice president for development at the Kennedy Center. “But you’re always looking for the next person: They’re not the ones getting 400 invitations. Maybe they’re only getting a dozen invitations. So we invite them to the center.” And with luck, they’ll start donating.

“There’s a coming-of-age aspect of philanthropy,” says Wolf Trap president Arvind Manocha. At a certain point in their lives — whether it’s through chance, peer pressure, professional networking or actual charity — the socially inclined naturally seek out causes and institutions that they enjoy and that reflect well on them.

But most 20-somethings aren’t looking to land on a social list; they’re looking for a good time.

The dance floor in a tent at the annual Meridian Ball at the Meridian House in Washington. (Deb Lindsey/For The Washington Post )

The idea of throwing a party for fun — no cause, no agenda — is so rare that the annual “Welcome Home” party hosted by real estate mogul Calvin Cafritz and his wife, Jane, every September is a rare unicorn in a field of fundraising ponies. For years, the couple has invited a long list of friends, most returning to the capital after spending the summer away, to eat, drink and dance in their Georgetown home.

Fun is the great unspoken factor in this modern frenzy of philanthropy. People, even very rich people doing Important Things, like to have a good time.

White House state dinners, for those lucky enough to receive an invitation, are fun. The frenzied red-carpet rubbernecking of the White House Correspondents’ Association dinner every spring is fun, at least the first time. Embassies and the ambassadors who preside over them can be fun, especially since they’re something that no other city can offer.

There’s a glamour associated with embassies in Washington, partly because they’re in some of the most impressive mansions in the nation’s capital. The ambassadors from the countries that are traditional U.S. allies — France, Great Britain, Italy, Ireland and Israel — get A-list status by simply presenting their credentials. Invitations to most embassies are highly coveted, but the parties reflect the personalities of their hosts. The current French ambassador, Gérard Araud, has created a lively salon, throwing open his Kalorama residence for receptions and dinners on a regular basis. Rima al-Sabah, wife of the Kuwaiti ambassador, is renowned for her A-list dinners filled with Cabinet secretaries, White House officials, corporate heavyweights and the occasional movie star.

Embassies also play a huge role in the appeal of the Meridian Ball, which started as a black-tie waltz 48 years ago to support Meridian International Center, a global leadership organization. The ball was run by a succession of socially prominent women who vied for the honor to chair the event. Patrons were invited to embassy dinners around town, then gathered at the center’s beaux-arts mansion off 16th Street for dancing. It was always elegant, but not always memorable.

About 20 years ago, organizers added a dinner at the White-Meyer House, the property next door. The idea was to introduce the ball to younger patrons who would dine in an English country house setting and mingle with the big donors coming from the embassy dinners. The experiment was such a success that many of the same people, now in their 40s and 50s, are skipping the embassies so that they can hang out with their friends. (The embassy dinners, however, remain an important draw for the corporate crowd.)

About 10 years ago, the ball added a tent and a DJ on the back lawn, thinking that it would appeal to the younger crowd. Now it’s the most popular part of the party: lights low, the champagne flowing, the dance floor jammed all night with couples of all ages.

“There’s very little asked of the guest other than to have fun,” explains center president Stuart Holliday. “There are so few true parties.”

What looks like effortless fun is based on dozens of strategic decisions by Holliday and his team. October’s ball featured no speeches, no silent auctions, no heartfelt appeals. Despite the shift to increasingly casual parties, this one remains black tie, because there’s a level of glamour that comes with dressing up.

Holliday is not only competing with dozens of other charities for those fundraising dollars, he is also competing with a new social draw: the District’s vibrant food scene. People who used to socialize at charity dinners now have literally hundreds of options for entertaining friends at restaurants. His job is to convince them that the Meridian Ball is a “destination event” worth their time and money.

The choices are dizzying. There are more and more fundraisers every year; high-profile donors get invitations to four or five events on a single night. There’s incredible pressure for organizers to stand out and impress people who have seen it all. It’s not enough to be entertained. Guests need to be wowed.

Design Cuisine catered the East Wing opening and wanted to top the dinner it did for the National Gallery’s 75th anniversary in the spring. The museum borrowed Bernardaud chargers from the Calder Foundation; the menu was created to rival any three-star restaurant. Guests actually gasped when waiters walked in with the dessert served under foot-high domes.

Design Cuisine co-founder Bill Homan has watched Washington go from discreet home dinners to events at historical venues — say, Mount Vernon — hosted by CEOs looking for something more interesting than a hotel ballroom or a restaurant. Business is booming: The past two to three years have been the best since the company was founded in 1981.

“There’s just so many more people with so much more money,” Homan says.

Under Armour founder Kevin Plank welcomes 2,000 guests to Fight Night at the Washington Hilton. (Deb Lindsey/For The Washington Post)

Kevin Plank walked into the Washington Hilton ballroom a happy man. The 44-year-old billionaire founder of athletic-wear giant Under Armour chaired the 28th Fight Night in November, a celebration of boxing, cigars, steaks and all things testosterone.

The party raised $5 million for local children’s charities before it even started, “and we’ll see how much more,” said Plank with a big smile. “It’s a great night for the city.”

When the late real estate investor Joe Robert founded the event, part of its appeal was the shocking lack of concern for traditional Washington society or sensibilities. With ring girls, booze and brawn, Robert invited his real estate and tech buddies to enjoy their success in a fun — and politically incorrect — boys’ night out.

The rest, of course, is history: The event thrived as the private-sector economy grew, drawing big money, big names and even the occasional politician. When Robert died in 2011, Raul Fernandez, vice chairman of Monumental Sports & Entertainment, picked up the torch.

This year’s event was once again sold out; the 2,000 guests, mostly business professionals, included Washington Mayor Muriel Bowser, Sen. Mark Warner of Virginia, Redskins cheerleaders and dozens of gorgeous young table hostesses clad in skintight red evening gowns.

It’s “the most fun night” of the year, said Republican strategist and MSNBC pundit Steve Schmidt, taking a much-needed break from election postmortems in a politics-free zone.

“Anytime people get down about this country, think about Kevin Plank,” he said. “Think about Under Armour. It shows you anything is possible in America.”

Roxanne Roberts is a Washington Post staff writer.