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For the record

  • Who: Code based on Navajo

  • What: Hardest code to crack

  • Where: Japan

During the Second World War, a combination of Navajo - the Native American language - along with fairly simply encryptions and a number of word substitutions provided the US Marine Corps with a fast and unbreakable code that could be used to communicate within 20 seconds what would otherwise take around 30 minutes using traditional coding machines.

The code substituted Navajo words for common military terms - so “tank” became the Navajo word for “turtle” - and spelled out letters using Navajo words based on the first letter of the English translation of the word, i.e. “Wo-la-chee” means “ant” or “A”. During the first 48 hours of the battle for the Pacific island of Iwo Jima, Navajo Code Talkers transmitted over 800 coded messages with perfect accuracy and without a single message being successfully decoded by the enemy.


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