Collar brass refers to the military emblems that are worn on the military uniform. On the right side of the collar is the national emblem: U.S. On the left side of the collar is the branch insignia which denotes membership in a particular area of expertise. The first use of Army branch insignia was just prior to the American Civil War in 1858 for use on the black felt hat. By the start of the 20th century, Army personnel began wearing various branch insignia on the stand-up collars of the Army dress uniform. Branch insignia was also worn by officers on the wool uniform shirt when worn as outerwear. Enlisted soldiers wore a version enclosed in a brass disk while officers wore a full sized version not enclosed. This has continued to the present time.
