What year did the U.S. Army start issuing dog tags?
During the Civil War, more than 25% of soldiers killed during battle were left unidentified. Soldiers had to come up with their own ways of being identified, some would write their names on the soles of their shoes, some wore pins. During the Spanish-American War, chaplain Charles-Pierce pushed to make official tags after seeing the sea of deceased soldiers come through his morgue unidentified. In 1906, implementing official dog tags became a requirement of the military and 25% of unidentified soldiers dropped to 2% during World War I. Source: The New York Times