The Island of the Day Before (Italian: L'isola del giorno prima) is a 1994 novel by Umberto Eco. An English translation (ISBN 0-14-025919-8) was written by William Weaver. It is the story of a 17th century Italian nobleman, Roberto della Griva, who is the only survivor of a shipwreck during a fierce storm.
Roberto della Griva finds himself washed up on an abandoned ship in a harbor through which, he convinces himself, runs the International Date Line. Although he can see land, his inability to swim leaves him marooned and he begins to reminisce about his life and his love. He becomes obsessed about his allegedly evil twin brother, who is split from his own persona through a process reminiscent of the doppelganger effect, and thus accusing him of all the bad things that happened in his life. The brother takes blame mainly for his bad choices and is present to sweeten the disappointments of life . Through this reminiscence he becomes convinced that all his troubles will end, if only he can reach the land. The story is told from the point of view of a modern editor who has sorted through the man's papers. Exactly how the papers were preserved and eventually handed down to the editor remains a point of conjecture.
"I take pride withal in my humiliation, and as I am to this privilege condemned, almost I find joy in an abhorrent salvation; I am, I believe, alone of all our race, the only man in human memory to have been shipwrecked and cast up upon a deserted ship."
- page 1, Roberto della Griva, Umberto Eco, trans. William Weaver. Penguin Books, 1996.