Beneath the Vatican's Belvedere courtyard, just a few feet below ground, lies the skeletal remains of an elephant. Yes, an elephant. The story of how and why it got there is an especially peculiar chapter of papal history.

The skeleton was discovered in 1962, writes Sarah Laskow for Atlas Obscura, while maintenance workers were installing a heating and cooling system. It dates back to the 16th century, when Giovanni di Lorenzo de' Medici became Pope Leo X. At the time, Christian rulers would present gifts to the Vatican to curry favor; when Pope Leo X was elected in 1513, Manuel I, the king of Portugal, decided he would outdo all of his rivals.

Manuel wanted to expand Portugal's control of shipping routes to India, Laskow explains, which threatened an overland monopoly that belonged to Egyptian traders. Hoping to sway Pope Leo X to his side, Manuel sent a caravan of rare goods to the Vatican, laden down with gold, jewels and textiles — as well as an Indian elephant named Hanno.

Though Europeans knew elephants existed, the animal hadn't been seen since the days of the Roman Empire. Manuel brought elephants back to the continent, demanding a tribute of 10 each year from his vassals, Almudena Pérez de Tudela and Annemaria Jordan Gschwend write for the journal Early Modern Zoology. Hanno wasn't the only animal gifted to Leo X by Portugal — Manuel also sent a cheetah, leopards and a Persian horse — but the elephant certainly drew the most attention. Laskow writes:

Hanno arrived in Rome just before he was scheduled to appear before the Pope. And in his first official appearance, he made an equally dramatic impression. Walking through the streets of Rome adorned with handsome vestment and with a silver tower on his back, Hanno dropped to his dropped to his knees and bowed his head low upon reaching the Pope, before lifting back up to trumpet three times in the air. Then he sucked water into his trunk and sprayed water down on everyone assembled—including the Pope, who thought the whole of the elephant's performance delightful.

The pope was so taken with Hanno that he personally thanked Manuel, writing in a letter, "The sight of this quadruped provides us with the greatest amusement and has become for our people an object of extraordinary wonder." When the elephant died just two years later, Leo X was devastated; he wrote a lengthy epitaph and commissioned a memorial fresco from the artist Raphael.

Leo X's extravagant affection for Hanno also fueled disapproval of the Catholic Church. The elephant became the basis for an early criticism published by Martin Luther's followers, while satirists jokingly compared Hanno's treatment to the relics of the saints, Smithsonian historian Silvio A. Bedini writes in "The Pope's Elephant."

Hanno's skeleton still lies beneath the Vatican courtyard where he was buried centuries ago, although he's missing his tusks — they were removed and are reportedly stored somewhere else. To learn more about Pope Leo X's favorite pet, check out Laskow's story.