In May 1941, the German battleship Bismarck was sunk by the Royal Navy after a dramatic pursuit across the North Atlantic. Among the very few survivors recovered from the wreckage was an unnamed black-and-white cat, clinging to a floating board. British sailors retrieved him, described the animal as "quite unperturbed" by his ordeal, and brought him aboard HMS Cossack.
The cat — given the name Oscar, though later called Sam — settled into life aboard the Cossack. Then, in October 1941, HMS Cossack was struck by a German torpedo. The ship was badly damaged and eventually sank. Oscar survived.
He was transferred to the aircraft carrier HMS Ark Royal. Within weeks, the Ark Royal was also struck by a torpedo and sank. Oscar was found floating on a board again, described by a naval officer who spotted him as "angry but unharmed."
At this point, even the optimistic British Navy concluded that the cat was, if not actually cursed, at least statistically extraordinary in his capacity for disaster. He was posted to a shore position at the Governor's residence in Gibraltar, then eventually to a home for sailors in Belfast. He spent the rest of his life on dry land, reportedly gazing disdainfully out to sea.
Sam — his name was eventually settled as "Unsinkable Sam" — died in 1955. A pastel portrait of him, painted by Georgina Shaw-Baker, now hangs in the National Maritime Museum in Greenwich. He is recorded in the official lists of both the German Kriegsmarine (as the Bismarck's cat) and the Royal Navy.
The story raises an obvious question: how did a cat survive the sinkings of three major warships? The cynical answer is that cats are hydrophobic, extraordinarily good at floating, and small enough to be overlooked in the chaos of a sinking. The romantic answer — preferred by most who have heard the story — is simply that some creatures are harder to kill than battleships.