While many people remember the longstanding service of dogs in the military, many don't know that cats also played an important role in the first and second World Wars.
These brave felines proved to be fearless in the face of danger as they worked tirelessly to hunt and trap rodents in the trenches and on battleships.
During WWI, about 500,000 cats were employed by the British army to clear the trenches of mice and rats. The cats also saved thousands of lives by alerting troops to poisonous gas clouds.
While there are many impressive tales of heroic animals at war, none of them compare to the story of Unsinkable Sam...
Depending on who you are, Unsinkable Sam got his start in life on the wrong side of the ocean. The strikingly handsome black and white cat started his military "career" as a mouser in the fleet of the Nazi regime - the Kriegsmarine.
The spunky cat was more than just a master mouser though, he was also a survivor!
Amazingly, he served on and survived the sinking of the Bismarck (Nazis), the HMS Cossack (British) and the HMS Ark Royal (British).
The battleship, named after Chancellor Otto von Bismarck, launched on 14 February 1939 and lost in a tussle with allied battleship, The Prince of Wales.
The Bismarck could not no longer navigate and took on water. It sank and out of a crew of over 2,200, only 118 men and one cat survived.
The lucky feline was spotted hours later by the crew of the homeward-bound British destroyer HMS Cossack, who scooped him up off of a floating board.
Now a member of the Allied forces (and newly named Oscar), the lucky kitty spent the next few months 'working' as a mouser.
He carried out his duties as the ship crossed the Mediterranean and north Atlantic operating as a convoy escort.
Unfortunately, things went wrong and the destroyer was seriously damaged by a torpedo. There were 139 casualties, but, miraculously, Oscar escaped death once again!
The lucky guy was spotted, one again, floating on a piece of plank. Sailors brought him to Gibralter, where he was renamed Unsinkable Sam and posted for service on the HMS Ark Royal.
HMS Ark Royal
Now serving on the ship that was actually instrumental in sinking the Bismarck, Unsinkable Sam and the Ark Royal survived several near misses.
However, on their way home from Malta, on 14 November, 1941, the ship suffered a devastating torpedo blow from a U-boat.
Unsinkable Sam was rescued when someone spotted him clinging to a floating plank near a motor launch. Although he was described as "angry, but quite unharmed," it's clear that this kitty had enough of human war games.
Sam was transferred to a job inland where he spent the rest of his service hunting mice in the building of the Governor General in Gibraltar. He was eventually sent back to the United Kingdom where he lived at a 'Home for Sailors' in Belfast for the remainder of his days.
After a full, long life, Sam passed away peacefully in 1955.