On February 5, 1918, the U.S. 102nd Infantry reached the front lines of France at Chemin des Dames, north of Soissons. Heavy artillery gunfire and grenade assaults from the Central Powers soon followed. After days and nights of shelling, the exhausted U.S. soldiers fell asleep in vermin-infested trenches. It was then, in the early morning hours, when the German Army decided to unleash another attack: mustard gas.

Roused from his sleep, one member of the infantry's Yankee Division leaped into action. Stubby, a Staffordshire terrier mix ran from soldier to soldier, barking and alerting them to the danger. Stubby later attacked a German soldier as he was mapping out the layout of Allied trenches, leading to the spy's capture. 

By the end of World War I, Stubby had served in 17 battles and survived at least two life-threatening injuries—including shrapnel in his chest and leg. The rugged little canine would become the first dog to be given the rank—Sergeant—in the U.S. Armed Forces.

"Stubby's story transcends time, in that the story of a dog's loyalty, bravery and devotion to his human companions will always strike a chord with the American public, dog lovers that we are," says Kathleen Golden, curator of the National Museum of American History's Division of Armed Forces History. "Humans are fallible, but dogs are always true, and they will selflessly lay down their lives to protect what they love."

Ronald Aiello, president of the United States War Dogs Association, points out that Stubby was not even an official "war dog."

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"He was taken to Europe as a mascot and pet," Aiello says, explaining that Corporal Robert Conroy adopted the stray while training on the grounds of the Yale University campus in July 1917. Sergeant Stubby died in his sleep in 1926 at age 10, with his remains gifted to the Smithsonian Institution, where they remain on display.

While the Red Cross relied on working dogs during World War I, as did the German, British and French troops, only rare photos exist to document canines’ contributions to the war.