Historians are still piecing together what happened to Alexander Selkirk, upon whom Robinson Crusoe was based.
He had spent four years and four months on Más a Tierra, a windswept island in the Juan Fernandez archipelago, 650 kilometers (404 miles) off the coast of Chile. He was as alone as a human being can be. For Selkirk, there was no "Man Friday," a character Defoe created for his novel.
Selkirk was rescued by pirates and become one himself, making a fortune in the process. (via ny times ideas)