When you think of service animals, you probably think of dogs, right? Well, you might be surprised to learn that cats have a long history of helping humans too! Specifically, cats were once really important aboard ships. Back in the day, cats were brought aboard trading ships to control the rats and mice that could cause all kinds of problems on board, like destroying ropes, woodwork, food and grain cargo.

But cats weren’t just great at catching rodents. They also offered some much-needed companionship to sailors who were away from home for long periods of time. That’s why we’ve put together a list of four of the most celebrated cats who have ever served at sea.

Blackie was the ship cat for HMS Prince of Wales, a battleship of the Royal Navy during World War II. He was famously photographed with Winston Churchill after the Prime Minister was brought to the ship for a secret meeting with Franklin D. Roosevelt.

Unsinkable Sam was the ship’s cat aboard the German battleship Bismarck. When the ship was sunk in 1941, only 116 out of a crew of more than 2,200 survived — 117 if you include Sam! Sam was picked up by the destroyer HMS Cossack, which was in turn torpedoed and sunk a few months later. Sam then became the ship’s cat of HMS Ark Royal, which was torpedoed and sunk in November of that year. Sam was rescued once again, but after that incident, it was decided that it was time for him to retire.

Simon was the celebrated ship’s cat of HMS Amethyst. During the Yangtze Incident in 1949, Simon was wounded in the bombardment that killed 25 crewmembers, including the commanding officer. Simon recovered and resumed his rat-hunting duties, as well as keeping up the crew’s morale. He was appointed to the rank of able seacat and posthumously awarded the Dickin Medal for bravery.

Mrs. Chippy was a tiger-striped tabby who was taken on board the ill-fated Endurance by Harry McNeish, a carpenter nicknamed “Chippy.” Because the cat followed McNeish around like a jealous wife, the cat was affectionately called Mrs. Chippy despite being a male cat. He would explore the Arctic expanse with McNish, Sir Ernest Shackleton, and the rest of the crew.

Cats might not seem like the most likely candidates for service animals, but these four felines prove that they were once some of the most valuable members of any ship’s crew. We hope this fun and informative article has made you smile and appreciate these furry helpers who were once unsung heroes of the high seas!