Navajo volunteers were an elite group recruited by the Marines to create the only unbroken code in modern military history. At the time the young men did not know that the Japanese had been able to break U.S. military codes.
"The Japanese knew everything about what we're planning against them," said Bill Toledo, a Navajo code talker.
The Navajo language was the solution. In 1942, 29 Navajos were called to duty to pass military messages on the battlefield. The so-called "Original 29" were the first to be taught an undecipherable code based on their complicated native language. It was a language some had been told to stop using.
"We were told to forget your language," said 89-year-old Samuel Tso. "Forget your culture. For some reason, I can't forget it. It's already in me and I can't forget it."
"I had memorized all of the codes we learned in the war in the school. It's all in my head," added Toledo.
The code had no alphabet and it could not be written down. Its complexity paid off during the U.S. invasion of Iwo Jima.
"'The sheep's eye is cured.' It makes no sense to anybody, even the Navajo people. But, it means Mt. Suribachi is secure," said Tso.
Less than 60 of the more than 400 code talkers are still alive, and they're still talking about the code and their military service.
"When I identify myself as a Navajo, I am really proud of who I am," Tso said.
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