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When the billionaire buyout titan Stephen A. Schwarzman gave himself a boom-era-defining 60th birthday party in 2007, the global economy was soaring.

Four years and one financial crisis later, the world looks very different. But not much has changed in the private equity world — at least when it comes to birthday parties.

Last Saturday night, the financier Leon D. Black celebrated his 60th with a blowout at his oceanfront estate in Southampton, on Long Island. After a buffet dinner featuring a seared foie gras station, some 200 guests took in a show by Elton John. The pop music legend, who closed with “Crocodile Rock,” was paid at least $1 million for the hour-and-a-half performance.

“The great Sir Elton John performing at my friend Leon Black’s fabulous 60th bday,” wrote the fashion designer Vera Wang on her Facebook page. “I had the honor of dressing his wife, my friend, Debra Black, the hostess! If there was ever a great family … this was it! Xx Vera”

The stars of music and fashion collided with a who’s who of Wall Street. Revelers included Michael R. Milken, the junk-bond pioneer and Mr. Black’s boss at Drexel Burnham Lambert in the 1980s; Julian H. Robertson Jr. , the hedge fund investor; Lloyd C. Blankfein, the chief executive of Goldman Sachs; and Mr. Schwarzman, head of the Blackstone Group.

Rounding out the guest list were politicians including Mayor Michael R. Bloomberg and Senator Charles E. Schumer of New York, who rubbed elbows with media celebrities like Martha Stewart and Howard Stern.

“Leon throws some good parties, because Leon’s worth like twenty gazillion, like twenty billion or something crazy, and for him, you know, a billion dollars is like ten dollars to us,” Mr. Stern said on his Monday show on SiriusXM Radio. Mr. Black sits on the company’s board.

Opulent celebrations thrown by the rich and famous are de rigueur in New York and Hamptons society. And in buyout land, there is something about private equity bosses and 60th birthdays: In 2002, David Bonderman, co-founder of TPG, had the Rolling Stones and John Mellencamp play at his celebration at the Hard Rock in Las Vegas.

But where Mr. Schwarzman’s $3 million birthday party came to be seen as a symbol of a new Gilded Age, a party like Mr. Black’s — at this moment in time — appears to some to be something else.

“It displays a kind of moral bad taste given the vast economic problems in the country,” said Michael M. Thomas, a former Lehman Brothers partner who writes novels about Wall Street. “This behavior suggests they are isolated from the rest of the world, living behind these great big hedges, and in a way they are.”

Mr. Black is no parvenu, having been a fixture on Wall Street for decades. When Drexel collapsed in the late 1980s, Mr. Black started a firm to buy stakes in troubled companies. Today, that firm, Apollo Global Management, manages $72 billion in assets and is publicly traded. Its holdings include Caesars Entertainment, the world’s largest casino company, and LyondellBasell, a big plastics and chemicals business.

Mr. Black, a major philanthropist to various scholastic, medical and cultural institutions, has also used his riches to amass a world-class art collection. In 2009, at a Christie’s auction, he paid about $47 million for a chalk drawing by Raphael of a woman’s head.

While much of the nation’s economy has struggled to recover from the financial crisis, Mr. Black’s firm — and the rest of the private equity industry — has snapped back. Though their deals are a far cry from the record takeovers struck in the last decade, multibillion-dollar buyouts have returned as banks extend corporate loans again. And pension funds and global sovereign wealth funds, faced with poor performance in stocks and bonds, continue to commit billions to private equity in the hopes of juicing their returns.

Apollo has long been considered one of Wall Street’s most skilled investors. The firm made a killing during the financial crisis. Its big bet on distressed debt at the market bottom in 2009 earned the firm and its clients billions of dollars in profits.

The industry’s continued success has made it a target in Washington. At issue is the low 15 percent tax rate paid by private equity executives on “carried interest,” or the share of profits that fund managers receive as part of their compensation. Eliminating this provision would raise $21 billion over the next decade, according to the Congressional Budget Office.

Mr. Black, speaking at a conference early last year, said he was resigned to a tax increase, saying that “it wouldn’t be the worst thing in the world for some adjustment.”

Yet he has also been an outspoken opponent of certain proposals that would raise taxes on him and the private equity industry. Last year, Mr. Black visited Capitol Hill to meet with lawmakers and make his case.

Mr. Black, through a spokeswoman, declined to comment.

On Saturday night, to be sure, there was little talk of carried interest at the Blacks’ home on Meadow Lane, one of the Hamptons most desirable addresses for its panoramic views of the Atlantic Ocean and Shinnecock Bay. He counts among his neighbors Calvin Klein and David H. Koch, the billionaire industrialist.

Mr. Black had his backyard transformed into a faux nightclub setting, constructing a wooden deck over his swimming pool and building a tent for Mr. John’s concert. After a buffet of crab cakes and steak, partygoers sat on couches with big puffy pillows. They watched Mr. Black’s four grown children deliver touching toasts to their father, including a poem by the youngest son.

“Oh, I wish I was Leon Black’s child,” Mr. Stern said on Monday.

Mr. John then took the stage and performed many of his hits, including “Your Song,” “Benny and the Jets” and “Candle in the Wind.” He joked that he knew how important 60th birthday parties were because he recently had one. (He is 64.)

Before the concert, around 8 p.m., as a full moon rose over the Atlantic, Mr. Blankfein and Mr. Schwarzman stood at the foot of the stairs leading down to the beach. Guests overheard Mr. Blankfein playfully ribbing Mr. Schwarzman about his fin de siècle affair.

“Your 60th got us into the financial crisis,” Mr. Blankfein is said to have told the private equity titan. “Let’s hope this party gets us out of it.”