A bust of the Emperor Caligula. (Museo Archeologico dei Campi Flegrei, Baia)

The utility of an antique coffee table in a Manhattan apartment took a sudden, historic turn when New York prosecutors swung by to pick it up.

No, they hadn’t seen it on Craiglist, thinking, “Wow, that marbled mosaic coffee table would look fantastic in the law library.”

The Manhattan District Attorney’s Office was helping Italian authorities, who said the coffee table was actually a mosaic that decorated a pleasure barge belonging to Emperor Caligula in about A.D. 37. If you think this sounds like fake news, here’s the Friday news release describing the whole thing.

If Caligula doesn’t ring a bell, you probably slept through the Roman Empire portion of history class. You almost certainly don’t speak Latin. And maybe you also missed one of several controversial movies about his depraved life, one of which earned this heartfelt review from Roger Ebert: “sickening, utterly worthless, shameful trash.”

As a historical aide, here are a few Retropolis-style CliffsNotes on Caligula, based on legends passed down through the ages:

His claim to fame: “Rome’s most tyrannical emperor.”

What he looked like: “Tall, pale and so hairy that he made it a capital offense to mention a goat in his presence. He worked to accentuate his natural ugliness by practicing terrifying facial expressions in a mirror.”

Prior experience qualifying him to be emperor: None in “government, diplomacy or war.” (He was ahead of his time.)

• Once declared:  He was a living God.

Interests: Silk gowns, dressing as a woman, sex, more sex, and “rolling around in piles of money and drinking precious pearls dissolved in vinegar.”

Close relationship with animals: “Appointed his horse as a consul.”

How he died: “Stabbed 30 times. … His body was dumped into a shallow grave, and his wife and daughter were murdered.” (This was ordered by the Praetorian Guard, not Tony Soprano.)

Of all the dastardly things Caligula was known for, his pleasure barges were the most infamous. The Telegraph newspaper in London reports:

They were essentially floating palaces, decorated with gold, marble and mosaic floors and boasting luxurious facilities such as heating and plumbing.

They were said to have been equipped with sails made of purple silk and had richly-decorated prows.

The onboard entertainment may even have extended to orgies.

Which brings us to the mosaic.

The mosaic that decorated Caligula’s pleasure barge and had been turned into a coffee table. (Courtesy of the New York District Attorney’s Office)

“The marble flooring section, which dates back to 35 A.D., was originally part of an ornate ship commissioned by the Roman emperor Caligula at Lake Nemi,” according to the Manhattan District Attorney’s Office. “Following the emperor’s assassination, the ship sank and remained underwater for nearly 2,000 years, until it was excavated in the 1920s.”

Which gets us to the part of the story about Italian dictator Benito Mussolini, as told by the Telegraph:

The mosaic was recovered from Lake Nemi, in the Alban Hills outside the capital, between 1928 and 1932 during an archaeological operation that was ordered by Benito Mussolini.

It was put on display in a museum inaugurated by Mussolini in 1940. But in 1944, during fighting between the Allies and the retreating Germans, a fire broke out and the museum burned to the ground. The mosaic may have been stolen during the chaos of war.

Which gets us to Manhattan.

The Telegraph says:

It had been bought in the 1960s by Helen Fioratti, an antiques dealer, and her husband Nereo Fioratti, a foreign correspondent for an Italian newspaper, and kept in their Park Avenue apartment. They said they bought the piece in good faith from an aristocratic family and for years used it as a coffee table.

Imagine, just for a moment, what the Nielsen ratings would have been had this episode played out on “Antiques Roadshow.”

Meanwhile, the legend of Caligula lives on in 2017 through none other than fallen Hollywood mogul Harvey Weinstein, who has been accused of sexual harassment and assault by dozens of women.

“The Caligula of Cannes,” The Guardian called him.

As for the mosaic, it is headed back to Italy, its reign as a coffee table exhausted.

Read more Retropolis:

The Salem witch trials: Why everyone from Trump to Woody Allen still invokes their hysteria

‘I am ready’: Mata Hari faced a firing squad for spying — and refused a blindfold.

Missouri v. Celia, a Slave: She killed the white master raping her, then claimed self-defense

O.J.’s last defender — F. Lee Bailey — is broke, disbarred and working above a hair salon

Hugh Hefner, the murder of Dorothy Stratten and the dark side of Playboy