[tongyun]

In my humble opinion, this is one of the most creative methods of cryptology that took place during WW II. Philip Johnston came up with the idea of using Navajo based upon his experience as the son of a missionary living on the Navajo reservation. He thought the language would be difficult to decipher because of how complex it was and very few non-Navajos knew how to speak the language. It was a language the Japanese could never break and helped the U.S. Marines in their battles on Guadalcanal, Tarawa, Peleliu, Iwo Jima.