As a gift for Jeffrey Epstein’s 63rd birthday, friends sent letters in tribute to the wealthy financier and convicted sex offender. Several shared a common theme: recounting the dinner gatherings that Mr. Epstein regularly hosted at his palatial townhouse on Manhattan’s Upper East Side.

Ehud Barak, former prime minister of Israel, and his wife noted the great diversity of guests. “There is no limit to your curiosity,” they wrote in their message, which was compiled with others in January 2016. “You are like a closed book to many of them but you know everything about everyone.”

The media mogul Mortimer Zuckerman suggested ingredients for a meal that would reflect the culture of the mansion: a simple salad and whatever else “would enhance Jeffrey’s sexual performance.”

And the director Woody Allen described how the dinners reminded him of Dracula’s castle, “where Lugosi has three young female vampires who service the place.”

But Mr. Epstein’s prized property was no gloomy Transylvanian fortress. He had spent years turning the seven-story, 21,000-square-foot townhouse into a place where he could flaunt — and deepen — his connections to the rich and powerful, even as hints of his dark side lurked within, according to previously undisclosed photos and documents showing how he lived in his later years.

Since Mr. Epstein’s death in federal custody in 2019, which was ruled a suicide, many mysteries about his life have remained unsolved. How did he amass a nine-figure fortune? And why did so many powerful men continue to fraternize with him long after he became a registered sex offender?

The White House had pledged to release details about the federal investigations into Mr. Epstein and his associates. But this summer the Trump administration backpedaled. The ensuing right-wing outrage has threatened to splinter the Make America Great Again movement — for whom Mr. Epstein is a central figure in conspiracy theories — and has put Mr. Trump on the defensive like few other issues.

Seeking to quell the backlash, the Justice Department dispatched a top official to meet with Ghislaine Maxwell, Mr. Epstein’s longtime associate who is serving a 20-year prison sentence for sex trafficking. On Friday, Ms. Maxwell was moved to a lower-security facility. That fueled speculation that Mr. Trump might commute her sentence or even pardon her in return for her cooperation.

For years, Ms. Maxwell was a fixture in Mr. Epstein’s New York townhouse, where she had an office. But she and Mr. Epstein had split by the mid-2010s. A framed photo in the townhouse showing Mr. Epstein with Mr. Trump and his then-girlfriend, Melania Knauss, was cropped to exclude Ms. Maxwell.

At least one other MAGA luminary also visited the townhouse: Stephen K. Bannon, a former adviser to Mr. Trump and an online media personality, who has said that he videotaped hours of interviews in the mansion with Mr. Epstein in 2019. Framed photos of Mr. Bannon — including a mirror selfie snapped by Mr. Epstein — were kept in at least two rooms in the mansion.

The townhouse was one of five properties around the world owned by Mr. Epstein. After his release in 2009 from a Florida jail, where he served 13 months for soliciting prostitution from a teenager, the mansion served as both a personal hideaway and a salon where he could hold court with accomplished intellectuals, scientists and financiers, according to legal records and interviews with people who frequented the home. The visitors considered Mr. Epstein fun, smart and curious. Another perk: getting to mingle with the young, attractive women who roamed the property and worked as his assistants.

The townhouse, a stone’s throw from Central Park, was sold to Mr. Epstein in 1998 by Leslie H. Wexner, the billionaire owner of L Brands. Mr. Epstein renovated and redecorated the mansion in an eccentric style.

Dozens of framed prosthetic eyeballs lined the entryway. A sculpture of a woman wearing a bridal gown and clutching a rope was suspended in a central atrium.

In the ground-floor dining room, Mr. Epstein entertained a rotating cast of celebrities, academics, politicians and businessmen. The food could be mundane — sometimes nothing more than a buffet of Chinese takeout, Mr. Allen’s letter noted — but the events were anything but.

Photos show that guests sat in leopard-print chairs around a large rectangular table. Occasionally, attendees said in interviews, a magician performed. Sometimes, a chalkboard was wheeled out so a guest could sketch a diagram or write a mathematical formula. Epstein preserved a map of Israel drawn on a chalkboard with Mr. Barak’s signature, according to a photo reviewed by The New York Times.

Up a grand staircase was Mr. Epstein’s wood-paneled office, featuring a massive desk. Photos show a taxidermied tiger lounging on a lush rug.

In the office, according to photos reviewed by The Times, Mr. Epstein showcased a green first edition of “Lolita,” the 1955 novel in which an intellectual develops a sexual obsession with a 12-year-old girl and repeatedly rapes her. Atop a wooden sideboard were more framed photos, including one of Mr. Epstein with Saudi Arabia’s crown prince, Mohammed bin Salman.

Several of Mr. Epstein’s victims have said the mansion was outfitted with a network of hidden video cameras.

In the massage room were paintings of naked women, a large silver ball and chain, and shelves stocked with lubricant, according to photos reviewed by The Times. Mr. Epstein regularly directed teenage girls — some recruited from middle schools in Queens — to massage him while he was naked. Sometimes he masturbated in front of them, according to court records and interviews with victims. Sometimes he raped or assaulted them.

No surveillance cameras were visible in the photos of the massage room.

An earlier collection of letters, presented to Mr. Epstein in a leather-bound album for his 50th birthday in 2003, reflected an era of his life before he was first arrested. That book included contributions from Mr. Trump and Mr. Clinton, among dozens of others, The Wall Street Journal reported. (Mr. Trump has denied a report in The Journal that he contributed a sexually suggestive note and drawing. He has sued the news organization for defamation. Mr. Clinton’s spokesman has said the former president was unaware of Mr. Epstein’s crimes.)

But by 2016, as Mr. Epstein’s reputation as a sexual predator became increasingly hard to ignore, his social network was shrinking. Three years later, he would die in a Manhattan jail while awaiting prosecution on federal sex-trafficking charges.

The Times reviewed seven birthday messages given to Mr. Epstein in 2016. In addition to those from Mr. Zuckerman, Mr. Allen and Mr. Barak, there were letters from the linguist Noam Chomsky and his wife; Joichi Ito, an entrepreneur who years later would resign from M.I.T. and the board of The New York Times Company because of his ties to Mr. Epstein; and Lawrence M. Krauss, a prominent physicist. Martin Nowak, a Harvard biologist, contributed a science-themed poem.

Mr. Zuckerman, Mr. Allen, Mr. Ito, Dr. Nowak and Mr. Bannon did not respond to requests for comment. Mr. Barak declined to comment. Dr. Chomsky’s wife responded on his behalf and declined to comment. Dr. Krauss said he didn’t recall the letter but attended “several lunches with very interesting discussions” with scientists, authors and others at Mr. Epstein’s home.

In their typed letter, Mr. Barak and his wife, Nili Priel, hailed Mr. Epstein as “A COLLECTOR OF PEOPLE.” The letter concluded, “May you enjoy long and healthy life and may all of us, your friends, enjoy your table for many more years to come.”

Susan C. Beachy contributed research. Production by Nico Chilla, Rebecca Lieberman, Eli Murray and Rumsey Taylor.