A Campaign hat has several distinctive features. One such feature is that the crown is pinched four times symmetrically. It could be made from felt or straw and, therefore, could be worn in varying seasons. Further, it has a wide brim and a high crown.
Even though the hat is also known as Stetson, it is not the same as a Stetson Cowboy hat. It was first made by the Stetson company and the Boss of the Plains hat, and therefore, it has got this name.
Campaign hat was a popular choice as part of the uniform of many armed forces, and was first used by the US Army in the mid-1800s.