A firefighter challenge coin is a special coin that expresses pride and fraternity among firefighters. The challenge coin tradition originated with soldiers in active combat where the coins served as identifying tokens signifying membership in an elite unit.
Americans stationed in Germany during World War II would challenge each other by slamming a coin on the bar when the check arrived for drinks. If a soldier did not have his coin, he had to buy a drink for the challenger and any other solider who was holding his coin. If all the other soldiers had their coins, the challenger had to buy everyone drinks. Police and fire departments picked up the tradition as a way to show pride in belonging to the department, according to Firehouse Coins.