Because, according to National Geographic, we didn’t remember him right the first time. Or at least we attribute a heck of a lot to the real-life castaway Alexander Selkirk that really needs to be reconsidered:
After Defoe’s death in 1731, some readers claimed the novel was inspired by Alexander Selkirk, a Scottish buccaneer who’d spent four and a half years on an island by himself. Today, many writers claim a connection between Selkirk and Crusoe.
But the idea that there’s a single, real Crusoe is a “false premise,” says Andrew Lambert, a naval history professor at King’s College London and author of Crusoe’s Island. That’s because Crusoe’s story is “a complex compound of all the other buccaneer survival stories.”
“Selkirk is definitely not accepted as the major source, or even one of the top five,” says Paula Backscheider, an English scholar at Auburn University and author of Daniel Defoe: His Life. “Robinson Crusoe is a long book and it is incorrect in dozens of ways to give Selkirk as the major source.”
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In Robinson Crusoe, the hero is the sole survivor of a shipwreck. He lands on an island by accident—but Selkirk chose to be left on an island.
Selkirk was a crew member on the Cinque Ports when it stopped at Más a Tierra, one of the Juan Fernández Islands off the coast of Chile, in 1704. There, Selkirk had an argument with the captain because he didn’t think that the ship was safe enough to keep sailing. Instead of leaving with the crew, Selkirk marooned himself on the island.
“The ship itself was in poor condition and he believed it would sink, which indeed it did,” Lambert says.
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In fact, one of the critical differences between Robinson Crusoe and earlier survival narratives like Selkirk’s is that its main character isn’t a pirate.
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In the 1960s, Chile changed the name of Más a Tierra, the island that Selkirk was marooned on, to Robinson Crusoe Island because of the presumed connection between Selkirk and Crusoe (it’s worth noting that the island in Robinson Crusoe has some Caribbean characteristics). They also changed the name of Más Afuera, a different island, to Alejandro Selkirk Island, even though Selkirk was never marooned there.