The use of Battle or Campaign Streamers are mostly indicative of The American Military. The practice was born out of the practice of embroidering the names of Battle and Engagements onto a Unit's Regimental Colors or related Flag. The first examples were seen in the 1920s.
Streamers are long pieces of multi-colored cloth (Silk and later Nylon), that are equally measured at 3-feet long with a width of 3-inches. As became tradition, each Streamer is in the Color of which each Battle is represented by. This tradition was culled from the various colors of the Ribbons and Medals which were given to Soldiers in a particular War or Battle. By way of example, The American Civil War is “identified” by the colors of “Blue and Gray”, hence The Battle Streamers are colors in that manner.
The Names of each Battle (regardless if it was a “victory” or not), are embroidered on a Streamer. In cases of long term “Wars”, often only a single Streamer is created – with the years of The War, placed. Currently, The US Army displays 187 Battle Streamers. Other Branches of The American Military (Air Force, Navy and Marines), also adopted Battle Streamers, with most doing so by the late 20th Century.
The display of Battle Streamers are regulated only to a particular Military Branches “Service Flag”. They are arranged to hang from the upper section of a Flag Pole, hanging downward. Other European Countries have adopted a similar practice in using Battle and Campaign Streamers from their Flags, with come applying them to their National Colors (as opposed to Regimental or Service Flags).