On November 14, 1883, pirates were born.

Well, pirates as we know them.

After months of serialization in the children’s magazine Young Folks, Robert Louis Stevenson’s “Treasure Island” was published as a novel on this day by Cassel & Co publishers. The swash-buckling tale of Jim Hawkins and Long John Silver was massively popular and first brought the notions of treasure maps, one-legged pirates, and parrots into the public’s imagination. Over the past 137 years, it has spawned over 50 movie and television adaptations, 24 stage performances, and countless tributes, from comic books to video games, and the book itself is still consistently listed among literary classics. There’s even a casino of the same name on the Las Vegas Strip (although its pirates would make even Blackbeard himself blush).

Our version of pirates–from Captain Hook to Captain Jack Sparrow–comes mainly from Stevenson’s tale. But…where did Stevenson’s tale come from? Did Long John Silver actually exist? Is there a real Treasure Island and, if so, where? And, most importantly, is there really buried treasure left to be found?

Some believe “Treasure Island” is based on the real-life murder of Captain George Glas on board the Earl of Sandwich in 1785. Learning of an abundance of treasure on the ship, several members of the crew mutinied, killing Glas, throwing his family overboard, and stealing the riches, which they later buried. Stevenson grew up next door to the Glasite Church in Edinburgh, members of the congregation set up by the victim’s father, so it seems an almost certainty that he was familiar with the crime.

Still others believe the inspiration came from the real-life ship Walrus. In Stevenson’s book, Captain Flint and his crew accumulated an enormous amount of captured treasure and sailed their ship–coincidentally called the Walrus–to an island somewhere in the Caribbean Sea, where they buried it. The real-life Walrus was overrun by pirates off the island of La Graciosa near Tenerife, who stole the treasure and buried it in an unknown location before being killed in skirmish with the British Navy; the treasure has never been found.

Other theories include Isla de Pinos near Cuba, which served as a supply base for pirates for about 300 years; Unst, one of the Shetland Islands, to which the map of Treasure Island bears a very vague resemblance; and Cocos Island off Costa Rica. British trader Captain William Thompson buried the stolen treasury of Peru there in 1820, and it has never been found, despite more than 300 expeditions to the island. Stevenson mentioned the buried treasure and Captain Thompson in a letter he wrote to W.E. Henley in 1881.

Still another, and perhaps most interesting, theory involves the Spanish ship Nuestra Señora de Guadalupe, which left Cuba on August 18, 1750 bound for Spain, carrying a cargo valued at nearly a million pieces of eight. A hurricane drove the ship over 500 miles off its intended course and, in early September 1750, it arrived instead at Teach’s Hole at Ocracoke Inlet, North Carolina. Also driven to the port by the hurricane were two merchant brothers, Owen and John Lloyd, who had been devastated by Spaniards in the recently ended King George’s War. In an act of supreme revenge, the brothers supposedly looted the ship of its massive treasure and slipped off into the night. According to legend, they buried the riches in various location in several chests on Norman Island, a deserted key in the British Virgin Islands.

It’s also worth mentioning that John Lloyd, one half the merchant-turned-pirate-brothers, had a peg leg. Just like a certain infamous character in Stevenson’s book.

Regardless of its inspiration, “Treasure Island” remains an enduring tale of adventure and mystery on the high seas. And its precisely the allure of the “what if” that keeps readers returning to its pages over and over again.

Because maybe, just maybe, ‘X’ really does mark the spot…