What is "natural" about a natural trumpet? Essentially, the length of its playing tube cannot be altered either by means of telescoping slides (as on the trombone) or by valves (as on the contemporary concert trumpet). But natural trumpets can still produces many notes, or pitches. By overblowing, you can play all the pitches in the overtone series of it's fundamental pitch For example, you can play the military "Taps" on a natural trumpet, because "this melody uses only a fundamental pitch and the first few pitches in its overtone series.
Natural trumpets come in many shapes, sizes and materials. European models tend to be made from wood or metal and either have long, straight tubes with bell-shaped ends, or s-shaped bodies for easier portability. Shepherds in Southern Poland use an instrument called a "trombita," a natural trumpet up to four meters long. In western Africa, families of ceremonial natural trumpets ranging in size from two to six feet have been made from elephant's tusks. In the South Pacific and other communities that had maritime trade routes, conch shell trumpets have been used.
These instruments have long had military and imperial connections. For example, ancient Egyptian natural trumpets have been discovered which bear inscriptions of Egyptian army divisions. In 14th and 15th century Europe, trumpeters were often tower watchmen for castles or military compounds. Those trumpeters who were under the direct jurisdiction of European sovereigns enjoyed a much higher social status than most musicians. In 1623, an exclusive Imperial Guild of Trumpeters and Kettle drummers was formed in Germany. The Guild had a dual purpose: to regulate and limit instruction on the trumpet, and to restrict where the trumpet could be played and by whom For a period of at least 50 years, less trumpet music was written down and printed for fear of unregulated performances by non-guild trumpeters!
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