Campaign Cords or Campaign Hat Cords are decorations generally worn around a variety of types of serviceman's hats to indicate station, unit, rank or history of service.They are generally used in the military or Police services, and mostly in the United States. Historically, they have been worn by the US military from the mid 19th century in the Indian campaigns, WW1, WW2 to a lesser degree in the pacific theatre, and by Air Cavalry in Vietnam. They are also worn by a number of US police highway patrol and Sheriffs.