Ace of Spades…..The card, associated with death, could be found among standard-issued card decks distributed to soldiers. The practice of putting those cards on the bodies of dead enemies began in Vietnam and was most probably initiated by American soldiers in the field.
Even though it became popular during the 1960s, the card’s use as a symbol dates earlier–to the days of World War II. It was the soldiers of the 101st Airborne Division who first started wearing helmets with an Ace of Spades emblem painted on them.
The reference, however, was different. For them, it was a good luck symbol, associated with good fortune in card playing. Also, since it was easily recognizable, the emblem served as a means of identification among friendlies.