The following is from an excerpt from the June 2014 National Geographic issue.
As long as men have been fighting wars, dogs have likely been somewhere on or near the battlefield. And more often than not, dogs have contributed bravely on the front lines, whether officially trained to do so or motivated by loyalty to soldiers.
The history of war dogs is deep: The Corinthians used them with success against the Greeks. The Romans used dogs to guard their legions and raise alarms, as did Attila the Hun, who placed them around his camps for added protection.
The United States military has lagged behind the rest of the world’s armies in using dogs, even though the idea was introduced early on. Benjamin Franklin made a somewhat lackluster attempt to advocate for using dogs (though more as weapons) in 1755.