The Dickin Medal is given to animals who show "conspicuous gallantry or devotion to duty" during wartime.  Most of the winners have been pigeons (they carried messages during World War II) or dogs, but there have also been a few horses and one cat.

Able Seacat Simon* of the HMS Amethyst was posthumously awarded the Dickin Medal in 1949 for removing a rat infestation and raising the sailors' morale, even after he was injured by a shell blast.

* not to be confused with Simon's Cat

I learned this by following this convoluted path on Wikipedia: Berber cuisine --> Pastilla --> Columbidae --> War pigeon --> Commando (pigeon) --> Dickin Medal --> Simon (cat)