U.S. Marines sometimes go by the nickname of devil dogs — a name given to them by the Germans in WWI. From War Creatures Timeline:
The U.S. Marine Corps earned an unofficial mascot during World War I that has remained an icon to this day. German soldiers reportedly referred to attacking Marines as teufel-hunden, or ‘devil-dogs’ because of their aggressive fighting tactics. Teufel-hunden were originally known as the wild, ferocious mountain dogs of Bavarian folklore.Upon hearing this, the Marines issued a recruiting poster depicted a snarling English bulldog wearing a Marine Corps helmet and a full-fledged mascot was born.
(Hat tip to The Adventures of Chester.)