Throughout history wars require secret messages being sent. Thus, encryption was born. Caesar ciphers, Spartan’s rolling stick, and other famous encryptions have been used. But one of the most famous by far would have to be the U.S. Marine’s Navajo code during WWII.
At the beginning of the war, need for a code was paramount. Pacific assault could not be conducted due to skilled Japanese and German cryptographers. Phillip Johnston, son of a missionary to the Navajo tribe, came up with the idea to encrypt the native Navajo language to transmit messages and troop orders.
Why? It was an unwritten language. There was no alphabet. No symbols. It was a dialect based spoken only language. Even better? Only about 30 people that were non native Navajo spoke it fluently. None of which were Japanese.
Approximately 400 Navajo code talkers were enlisted during the war. They have been attributed to one of the defining factors of the American capture of Iwo Jima. If not for their code, the war may have gone an entirely different way.
So how did it work? They took a stream of (for the most part) what sounded like arbitrarily jumbled together words in Navajo, translated it to English, and then took the first letter of each English translation. This led to even Navajo speakers not even being able to crack it.
“The Navajo code talkers even stymied a Navajo soldier taken prisoner at Bataan. (About 20 Navajos served in the U.S. Army in the Philippines.) The Navajo soldier, forced to listen to the jumbled words of talker transmissions, said to a code talker after the war, “I never figured out what you guys who got me into all that trouble were saying.””
Due to it’s value, the Navajo code talkers remained in service for years afterwords, only receiving honors in 1992- 50 years after most had enlisted.